fix: resolve linting issues in token efficiency implementation

- Fix ambiguous variable names (l → layer)
- Remove unused imports and variables
- Organize import statements

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.gitignore

@@ -174,3 +174,4 @@ cython_debug/
 # PyPI configuration file
 .pypirc
 
+data/

CLAUDE.md

@@ -1,255 +1,98 @@
-# CLAUDE.md
+# The Ouroboros
 
-This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+AI-powered trading agent for global stock markets with self-evolution capabilities.
 
-## Git Workflow Policy
+## Quick Start
 
-**CRITICAL: All code changes MUST follow this workflow. Direct pushes to `main` are ABSOLUTELY PROHIBITED.**
-
-1. **Create Gitea Issue First** — All features, bug fixes, and policy changes require a Gitea issue before any code is written
-2. **Create Feature Branch** — Branch from `main` using format `feature/issue-{N}-{short-description}`
-3. **Implement Changes** — Write code, tests, and documentation on the feature branch
-4. **Create Pull Request** — Submit PR to `main` branch referencing the issue number
-5. **Review & Merge** — After approval, merge via PR (squash or merge commit)
-
-**Never commit directly to `main`.** This policy applies to all changes, no exceptions.
-
-## Agent Workflow
-
-**Modern AI development leverages specialized agents for concurrent, efficient task execution.**
-
-### Parallel Execution Strategy
-
-Use **git worktree** or **subagents** (via the Task tool) to handle multiple requirements simultaneously:
-
-- Each task runs in independent context
-- Parallel branches for concurrent features
-- Isolated test environments prevent interference
-- Faster iteration with distributed workload
-
-### Specialized Agent Roles
-
-Deploy task-specific agents as needed instead of handling everything in the main conversation:
-
-- **Conversational Agent** (main) — Interface with user, coordinate other agents
-- **Ticket Management Agent** — Create/update Gitea issues, track task status
-- **Design Agent** — Architectural planning, RFC documents, API design
-- **Code Writing Agent** — Implementation following specs
-- **Testing Agent** — Write tests, verify coverage, run test suites
-- **Documentation Agent** — Update docs, docstrings, CLAUDE.md, README
-- **Review Agent** — Code review, lint checks, security audits
-- **Custom Agents** — Created dynamically for specialized tasks (performance analysis, migration scripts, etc.)
-
-### When to Use Agents
-
-**Prefer spawning specialized agents for:**
-
-1. Complex multi-file changes requiring exploration
-2. Tasks with clear, isolated scope (e.g., "write tests for module X")
-3. Parallel work streams (feature A + bugfix B simultaneously)
-4. Long-running analysis (codebase search, dependency audit)
-5. Tasks requiring different contexts (multiple git worktrees)
-
-**Use the main conversation for:**
-
-1. User interaction and clarification
-2. Quick single-file edits
-3. Coordinating agent work
-4. High-level decision making
-
-### Implementation
-
-```python
-# Example: Spawn parallel test and documentation agents
-task_tool(
-    subagent_type="general-purpose",
-    prompt="Write comprehensive tests for src/markets/schedule.py",
-    description="Write schedule tests"
-)
-
-task_tool(
-    subagent_type="general-purpose",
-    prompt="Update README.md with global market feature documentation",
-    description="Update README"
-)
-```
-
-Use `run_in_background=True` for independent tasks that don't block subsequent work.
-
-## Common Command Failures
-
-**Critical: Learn from failures. Never repeat the same failed command without modification.**
-
-### tea CLI (Gitea Command Line Tool)
-
-#### ❌ TTY Error - Interactive Confirmation Fails
-```bash
-~/bin/tea issues create --repo X --title "Y" --description "Z"
-# Error: huh: could not open a new TTY: open /dev/tty: no such device or address
-```
-**💡 Reason:** tea tries to open `/dev/tty` for interactive confirmation prompts, which is unavailable in non-interactive environments.
-
-**✅ Solution:** Use `YES=""` environment variable to bypass confirmation
-```bash
-YES="" ~/bin/tea issues create --repo jihoson/The-Ouroboros --title "Title" --description "Body"
-YES="" ~/bin/tea issues edit <number> --repo jihoson/The-Ouroboros --description "Updated body"
-YES="" ~/bin/tea pulls create --repo jihoson/The-Ouroboros --head feature-branch --base main --title "Title" --description "Body"
-```
-
-**📝 Notes:**
-- Always set default login: `~/bin/tea login default local`
-- Use `--repo jihoson/The-Ouroboros` when outside repo directory
-- tea is preferred over direct Gitea API calls for consistency
-
-#### ❌ Wrong Parameter Name
-```bash
-tea issues create --body "text"
-# Error: flag provided but not defined: -body
-```
-**💡 Reason:** Parameter is `--description`, not `--body`.
-
-**✅ Solution:** Use correct parameter name
-```bash
-YES="" ~/bin/tea issues create --description "text"
-```
-
-### Gitea API (Direct HTTP Calls)
-
-#### ❌ Wrong Hostname
-```bash
-curl http://gitea.local:3000/api/v1/...
-# Error: Could not resolve host: gitea.local
-```
-**💡 Reason:** Gitea instance runs on `localhost:3000`, not `gitea.local`.
-
-**✅ Solution:** Use correct hostname (but prefer tea CLI)
-```bash
-curl http://localhost:3000/api/v1/repos/jihoson/The-Ouroboros/issues \
-  -H "Authorization: token $GITEA_TOKEN" \
-  -H "Content-Type: application/json" \
-  -d '{"title":"...", "body":"..."}'
-```
-
-**📝 Notes:**
-- Prefer `tea` CLI over direct API calls
-- Only use curl for operations tea doesn't support
-
-### Git Commands
-
-#### ❌ User Not Configured
-```bash
-git commit -m "message"
-# Error: Author identity unknown
-```
-**💡 Reason:** Git user.name and user.email not set.
-
-**✅ Solution:** Configure git user
-```bash
-git config user.name "agentson"
-git config user.email "agentson@localhost"
-```
-
-#### ❌ Permission Denied on Push
-```bash
-git push origin branch
-# Error: User permission denied for writing
-```
-**💡 Reason:** Repository access token lacks write permissions or user lacks repo write access.
-
-**✅ Solution:**
-1. Verify user has write access to repository (admin grants this)
-2. Ensure git credential has correct token with `write:repository` scope
-3. Check remote URL uses correct authentication
-
-### Python/Pytest
-
-#### ❌ Module Import Error
-```bash
-pytest tests/test_foo.py
-# ModuleNotFoundError: No module named 'src'
-```
-**💡 Reason:** Package not installed in development mode.
-
-**✅ Solution:** Install package with dev dependencies
 ```bash
+# Setup
 pip install -e ".[dev]"
+cp .env.example .env
+# Edit .env with your KIS and Gemini API credentials
+
+# Test
+pytest -v --cov=src
+
+# Run (paper trading)
+python -m src.main --mode=paper
 ```
 
-#### ❌ Async Test Hangs
-```python
-async def test_something():  # Hangs forever
-    result = await async_function()
-```
-**💡 Reason:** Missing pytest-asyncio or wrong configuration.
+## Documentation
 
-**✅ Solution:** Already configured in pyproject.toml
-```toml
-[tool.pytest.ini_options]
-asyncio_mode = "auto"
-```
-No decorator needed for async tests.
+- **[Workflow Guide](docs/workflow.md)** — Git workflow policy and agent-based development
+- **[Command Reference](docs/commands.md)** — Common failures, build commands, troubleshooting
+- **[Architecture](docs/architecture.md)** — System design, components, data flow
+- **[Context Tree](docs/context-tree.md)** — L1-L7 hierarchical memory system
+- **[Testing](docs/testing.md)** — Test structure, coverage requirements, writing tests
+- **[Agent Policies](docs/agents.md)** — Prime directives, constraints, prohibited actions
 
-## Build & Test Commands
+## Core Principles
+
+1. **Safety First** — Risk manager is READ-ONLY and enforces circuit breakers
+2. **Test Everything** — 80% coverage minimum, all changes require tests
+3. **Issue-Driven Development** — All work goes through Gitea issues → feature branches → PRs
+4. **Agent Specialization** — Use dedicated agents for design, coding, testing, docs, review
+
+## Project Structure
+
+```
+src/
+├── broker/          # KIS API client (domestic + overseas)
+├── brain/           # Gemini AI decision engine
+├── core/            # Risk manager (READ-ONLY)
+├── evolution/       # Self-improvement optimizer
+├── markets/         # Market schedules and timezone handling
+├── db.py            # SQLite trade logging
+├── main.py          # Trading loop orchestrator
+└── config.py        # Settings (from .env)
+
+tests/               # 54 tests across 4 files
+docs/                # Extended documentation
+```
+
+## Key Commands
 
 ```bash
-# Install all dependencies (production + dev)
-pip install ".[dev]"
+pytest -v --cov=src              # Run tests with coverage
+ruff check src/ tests/           # Lint
+mypy src/ --strict               # Type check
 
-# Run full test suite with coverage
-pytest -v --cov=src --cov-report=term-missing
+python -m src.main --mode=paper  # Paper trading
+python -m src.main --mode=live   # Live trading (⚠️ real money)
 
-# Run a single test file
-pytest tests/test_risk.py -v
-
-# Run a single test by name
-pytest tests/test_brain.py -k "test_parse_valid_json" -v
-
-# Lint
-ruff check src/ tests/
-
-# Type check (strict mode, non-blocking in CI)
-mypy src/ --strict
-
-# Run the trading agent
-python -m src.main --mode=paper
-
-# Docker
-docker compose up -d ouroboros          # Run agent
-docker compose --profile test up test   # Run tests in container
+# Gitea workflow (requires tea CLI)
+YES="" ~/bin/tea issues create --repo jihoson/The-Ouroboros --title "..." --description "..."
+YES="" ~/bin/tea pulls create --head feature-branch --base main --title "..." --description "..."
 ```
 
-## Architecture
+## Markets Supported
 
-Self-evolving AI trading agent for Korean stock markets (KIS API). The main loop in `src/main.py` orchestrates four components in a 60-second cycle per stock:
+- 🇰🇷 Korea (KRX)
+- 🇺🇸 United States (NASDAQ, NYSE, AMEX)
+- 🇯🇵 Japan (TSE)
+- 🇭🇰 Hong Kong (SEHK)
+- 🇨🇳 China (Shanghai, Shenzhen)
+- 🇻🇳 Vietnam (Hanoi, HCM)
 
-1. **Broker** (`src/broker/kis_api.py`) — Async KIS API client with automatic OAuth token refresh, leaky-bucket rate limiter (10 RPS), and POST body hash-key signing. Uses a custom SSL context with disabled hostname verification for the VTS (virtual trading) endpoint due to a known certificate mismatch.
+Markets auto-detected based on timezone and enabled in `ENABLED_MARKETS` env variable.
 
-2. **Brain** (`src/brain/gemini_client.py`) — Sends structured prompts to Google Gemini, parses JSON responses into `TradeDecision` objects. Forces HOLD when confidence < threshold (default 80). Falls back to safe HOLD on any parse/API error.
+## Critical Constraints
 
-3. **Risk Manager** (`src/core/risk_manager.py`) — **READ-ONLY by policy** (see `docs/agents.md`). Circuit breaker halts all trading via `SystemExit` when daily P&L drops below -3.0%. Fat-finger check rejects orders exceeding 30% of available cash.
+⚠️ **Non-Negotiable Rules** (see [docs/agents.md](docs/agents.md)):
 
-4. **Evolution** (`src/evolution/optimizer.py`) — Analyzes high-confidence losing trades from SQLite, asks Gemini to generate new `BaseStrategy` subclasses, validates them by running the full pytest suite, and simulates PR creation.
+- `src/core/risk_manager.py` is **READ-ONLY** — changes require human approval
+- Circuit breaker at -3.0% P&L — may only be made **stricter**
+- Fat-finger protection: max 30% of cash per order — always enforced
+- Confidence < 80 → force HOLD — cannot be weakened
+- All code changes → corresponding tests → coverage ≥ 80%
 
-**Data flow per cycle:** Fetch orderbook + balance → calculate P&L → get Gemini decision → validate with risk manager → execute order → log to SQLite (`src/db.py`).
+## Contributing
 
-## Key Constraints (from `docs/agents.md`)
+See [docs/workflow.md](docs/workflow.md) for the complete development process.
 
-- `core/risk_manager.py` is **READ-ONLY**. Changes require human approval.
-- Circuit breaker threshold (-3.0%) may only be made stricter, never relaxed.
-- Fat-finger protection (30% max order size) must always be enforced.
-- Confidence < 80 **must** force HOLD — this rule cannot be weakened.
-- All code changes require corresponding tests. Coverage must stay >= 80%.
-- Generated strategies must pass the full test suite before activation.
-
-## Configuration
-
-Pydantic Settings loaded from `.env` (see `.env.example`). Required vars: `KIS_APP_KEY`, `KIS_APP_SECRET`, `KIS_ACCOUNT_NO` (format `XXXXXXXX-XX`), `GEMINI_API_KEY`. Tests use in-memory SQLite (`DB_PATH=":memory:"`) and dummy credentials via `tests/conftest.py`.
-
-## Test Structure
-
-54 tests across four files. `asyncio_mode = "auto"` in pyproject.toml — async tests need no special decorator. The `settings` fixture in `conftest.py` provides safe defaults with test credentials and in-memory DB.
-
-- `test_risk.py` (11) — Circuit breaker boundaries, fat-finger edge cases
-- `test_broker.py` (6) — Token lifecycle, rate limiting, hash keys, network errors
-- `test_brain.py` (18) — JSON parsing, confidence threshold, malformed responses, prompt construction
-- `test_market_schedule.py` (19) — Market open/close logic, timezone handling, DST, lunch breaks
+**TL;DR:**
+1. Create issue in Gitea
+2. Create feature branch: `feature/issue-N-description`
+3. Implement with tests
+4. Open PR
+5. Merge after review

docs/architecture.md

@@ -0,0 +1,191 @@
+# System Architecture
+
+## Overview
+
+Self-evolving AI trading agent for global stock markets via KIS (Korea Investment & Securities) API. The main loop in `src/main.py` orchestrates four components in a 60-second cycle per stock across multiple markets.
+
+## Core Components
+
+### 1. Broker (`src/broker/`)
+
+**KISBroker** (`kis_api.py`) — Async KIS API client for domestic Korean market
+
+- Automatic OAuth token refresh (valid for 24 hours)
+- Leaky-bucket rate limiter (10 requests per second)
+- POST body hash-key signing for order authentication
+- Custom SSL context with disabled hostname verification for VTS (virtual trading) endpoint due to known certificate mismatch
+
+**OverseasBroker** (`overseas.py`) — KIS overseas stock API wrapper
+
+- Reuses KISBroker infrastructure (session, token, rate limiter) via composition
+- Supports 9 global markets: US (NASDAQ/NYSE/AMEX), Japan, Hong Kong, China (Shanghai/Shenzhen), Vietnam (Hanoi/HCM)
+- Different API endpoints for overseas price/balance/order operations
+
+**Market Schedule** (`src/markets/schedule.py`) — Timezone-aware market management
+
+- `MarketInfo` dataclass with timezone, trading hours, lunch breaks
+- Automatic DST handling via `zoneinfo.ZoneInfo`
+- `is_market_open()` checks weekends, trading hours, lunch breaks
+- `get_open_markets()` returns currently active markets
+- `get_next_market_open()` finds next market to open and when
+
+### 2. Brain (`src/brain/gemini_client.py`)
+
+**GeminiClient** — AI decision engine powered by Google Gemini
+
+- Constructs structured prompts from market data
+- Parses JSON responses into `TradeDecision` objects (`action`, `confidence`, `rationale`)
+- Forces HOLD when confidence < threshold (default 80)
+- Falls back to safe HOLD on any parse/API error
+- Handles markdown-wrapped JSON, malformed responses, invalid actions
+
+### 3. Risk Manager (`src/core/risk_manager.py`)
+
+**RiskManager** — Safety circuit breaker and order validation
+
+⚠️ **READ-ONLY by policy** (see [`docs/agents.md`](./agents.md))
+
+- **Circuit Breaker**: Halts all trading via `SystemExit` when daily P&L drops below -3.0%
+  - Threshold may only be made stricter, never relaxed
+  - Calculated as `(total_eval - purchase_total) / purchase_total * 100`
+- **Fat-Finger Protection**: Rejects orders exceeding 30% of available cash
+  - Must always be enforced, cannot be disabled
+
+### 4. Evolution (`src/evolution/optimizer.py`)
+
+**StrategyOptimizer** — Self-improvement loop
+
+- Analyzes high-confidence losing trades from SQLite
+- Asks Gemini to generate new `BaseStrategy` subclasses
+- Validates generated strategies by running full pytest suite
+- Simulates PR creation for human review
+- Only activates strategies that pass all tests
+
+## Data Flow
+
+```
+┌─────────────────────────────────────────────────────────────┐
+│ Main Loop (60s cycle per stock, per market)                │
+└─────────────────────────────────────────────────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Market Schedule Check             │
+        │ - Get open markets                │
+        │ - Filter by enabled markets       │
+        │ - Wait if all closed              │
+        └──────────────────┬────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Broker: Fetch Market Data        │
+        │ - Domestic: orderbook + balance  │
+        │ - Overseas: price + balance      │
+        └──────────────────┬────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Calculate P&L                     │
+        │ pnl_pct = (eval - cost) / cost   │
+        └──────────────────┬────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Brain: Get Decision               │
+        │ - Build prompt with market data   │
+        │ - Call Gemini API                 │
+        │ - Parse JSON response             │
+        │ - Return TradeDecision            │
+        └──────────────────┬────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Risk Manager: Validate Order      │
+        │ - Check circuit breaker           │
+        │ - Check fat-finger limit          │
+        │ - Raise if validation fails       │
+        └──────────────────┬────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Broker: Execute Order             │
+        │ - Domestic: send_order()          │
+        │ - Overseas: send_overseas_order() │
+        └──────────────────┬────────────────┘
+                           │
+                           ▼
+        ┌──────────────────────────────────┐
+        │ Database: Log Trade               │
+        │ - SQLite (data/trades.db)         │
+        │ - Track: action, confidence,      │
+        │   rationale, market, exchange     │
+        └───────────────────────────────────┘
+```
+
+## Database Schema
+
+**SQLite** (`src/db.py`)
+
+```sql
+CREATE TABLE trades (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    timestamp TEXT NOT NULL,
+    stock_code TEXT NOT NULL,
+    action TEXT NOT NULL,          -- BUY | SELL | HOLD
+    confidence INTEGER NOT NULL,   -- 0-100
+    rationale TEXT,
+    quantity INTEGER,
+    price REAL,
+    pnl REAL DEFAULT 0.0,
+    market TEXT DEFAULT 'KR',       -- KR | US_NASDAQ | JP | etc.
+    exchange_code TEXT DEFAULT 'KRX' -- KRX | NASD | NYSE | etc.
+);
+```
+
+Auto-migration: Adds `market` and `exchange_code` columns if missing for backward compatibility.
+
+## Configuration
+
+**Pydantic Settings** (`src/config.py`)
+
+Loaded from `.env` file:
+
+```bash
+# Required
+KIS_APP_KEY=your_app_key
+KIS_APP_SECRET=your_app_secret
+KIS_ACCOUNT_NO=XXXXXXXX-XX
+GEMINI_API_KEY=your_gemini_key
+
+# Optional
+MODE=paper                    # paper | live
+DB_PATH=data/trades.db
+CONFIDENCE_THRESHOLD=80
+MAX_LOSS_PCT=3.0
+MAX_ORDER_PCT=30.0
+ENABLED_MARKETS=KR,US_NASDAQ  # Comma-separated market codes
+```
+
+Tests use in-memory SQLite (`DB_PATH=":memory:"`) and dummy credentials via `tests/conftest.py`.
+
+## Error Handling
+
+### Connection Errors (Broker API)
+- Retry with exponential backoff (2^attempt seconds)
+- Max 3 retries per stock
+- After exhaustion, skip stock and continue with next
+
+### API Quota Errors (Gemini)
+- Return safe HOLD decision with confidence=0
+- Log error but don't crash
+- Agent continues trading on next cycle
+
+### Circuit Breaker Tripped
+- Immediately halt via `SystemExit`
+- Log critical message
+- Requires manual intervention to restart
+
+### Market Closed
+- Wait until next market opens
+- Use `get_next_market_open()` to calculate wait time
+- Sleep until market open time

docs/commands.md

@@ -0,0 +1,156 @@
+# Command Reference
+
+## Common Command Failures
+
+**Critical: Learn from failures. Never repeat the same failed command without modification.**
+
+### tea CLI (Gitea Command Line Tool)
+
+#### ❌ TTY Error - Interactive Confirmation Fails
+```bash
+~/bin/tea issues create --repo X --title "Y" --description "Z"
+# Error: huh: could not open a new TTY: open /dev/tty: no such device or address
+```
+**💡 Reason:** tea tries to open `/dev/tty` for interactive confirmation prompts, which is unavailable in non-interactive environments.
+
+**✅ Solution:** Use `YES=""` environment variable to bypass confirmation
+```bash
+YES="" ~/bin/tea issues create --repo jihoson/The-Ouroboros --title "Title" --description "Body"
+YES="" ~/bin/tea issues edit <number> --repo jihoson/The-Ouroboros --description "Updated body"
+YES="" ~/bin/tea pulls create --repo jihoson/The-Ouroboros --head feature-branch --base main --title "Title" --description "Body"
+```
+
+**📝 Notes:**
+- Always set default login: `~/bin/tea login default local`
+- Use `--repo jihoson/The-Ouroboros` when outside repo directory
+- tea is preferred over direct Gitea API calls for consistency
+
+#### ❌ Wrong Parameter Name
+```bash
+tea issues create --body "text"
+# Error: flag provided but not defined: -body
+```
+**💡 Reason:** Parameter is `--description`, not `--body`.
+
+**✅ Solution:** Use correct parameter name
+```bash
+YES="" ~/bin/tea issues create --description "text"
+```
+
+### Gitea API (Direct HTTP Calls)
+
+#### ❌ Wrong Hostname
+```bash
+curl http://gitea.local:3000/api/v1/...
+# Error: Could not resolve host: gitea.local
+```
+**💡 Reason:** Gitea instance runs on `localhost:3000`, not `gitea.local`.
+
+**✅ Solution:** Use correct hostname (but prefer tea CLI)
+```bash
+curl http://localhost:3000/api/v1/repos/jihoson/The-Ouroboros/issues \
+  -H "Authorization: token $GITEA_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{"title":"...", "body":"..."}'
+```
+
+**📝 Notes:**
+- Prefer `tea` CLI over direct API calls
+- Only use curl for operations tea doesn't support
+
+### Git Commands
+
+#### ❌ User Not Configured
+```bash
+git commit -m "message"
+# Error: Author identity unknown
+```
+**💡 Reason:** Git user.name and user.email not set.
+
+**✅ Solution:** Configure git user
+```bash
+git config user.name "agentson"
+git config user.email "agentson@localhost"
+```
+
+#### ❌ Permission Denied on Push
+```bash
+git push origin branch
+# Error: User permission denied for writing
+```
+**💡 Reason:** Repository access token lacks write permissions or user lacks repo write access.
+
+**✅ Solution:**
+1. Verify user has write access to repository (admin grants this)
+2. Ensure git credential has correct token with `write:repository` scope
+3. Check remote URL uses correct authentication
+
+### Python/Pytest
+
+#### ❌ Module Import Error
+```bash
+pytest tests/test_foo.py
+# ModuleNotFoundError: No module named 'src'
+```
+**💡 Reason:** Package not installed in development mode.
+
+**✅ Solution:** Install package with dev dependencies
+```bash
+pip install -e ".[dev]"
+```
+
+#### ❌ Async Test Hangs
+```python
+async def test_something():  # Hangs forever
+    result = await async_function()
+```
+**💡 Reason:** Missing pytest-asyncio or wrong configuration.
+
+**✅ Solution:** Already configured in pyproject.toml
+```toml
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+```
+No decorator needed for async tests.
+
+## Build & Test Commands
+
+```bash
+# Install all dependencies (production + dev)
+pip install -e ".[dev]"
+
+# Run full test suite with coverage
+pytest -v --cov=src --cov-report=term-missing
+
+# Run a single test file
+pytest tests/test_risk.py -v
+
+# Run a single test by name
+pytest tests/test_brain.py -k "test_parse_valid_json" -v
+
+# Lint
+ruff check src/ tests/
+
+# Type check (strict mode, non-blocking in CI)
+mypy src/ --strict
+
+# Run the trading agent
+python -m src.main --mode=paper
+
+# Docker
+docker compose up -d ouroboros          # Run agent
+docker compose --profile test up test   # Run tests in container
+```
+
+## Environment Setup
+
+```bash
+# Create .env file from example
+cp .env.example .env
+
+# Edit .env with your credentials
+# Required: KIS_APP_KEY, KIS_APP_SECRET, KIS_ACCOUNT_NO, GEMINI_API_KEY
+
+# Verify configuration
+python -c "from src.config import Settings; print(Settings())"
+```

docs/context-tree.md

@@ -0,0 +1,338 @@
+# Context Tree: Multi-Layered Memory Management
+
+The context tree implements **Pillar 2** of The Ouroboros: hierarchical memory management across 7 time horizons, from real-time market data to generational trading wisdom.
+
+## Overview
+
+Instead of a flat memory structure, The Ouroboros maintains a **7-tier context tree** where each layer represents a different time horizon and level of abstraction:
+
+```
+L1 (Legacy)      ←  Cumulative wisdom across generations
+  ↑
+L2 (Annual)      ←  Yearly performance metrics
+  ↑
+L3 (Quarterly)   ←  Quarterly strategy adjustments
+  ↑
+L4 (Monthly)     ←  Monthly portfolio rebalancing
+  ↑
+L5 (Weekly)      ←  Weekly stock selection
+  ↑
+L6 (Daily)       ←  Daily trade logs
+  ↑
+L7 (Real-time)   ←  Live market data
+```
+
+Data flows **bottom-up**: real-time trades aggregate into daily summaries, which roll up to weekly, then monthly, quarterly, annual, and finally into permanent legacy knowledge.
+
+## The 7 Layers
+
+### L7: Real-time
+**Retention**: 7 days
+**Timeframe format**: `YYYY-MM-DD` (same-day)
+**Content**: Current positions, live quotes, orderbook snapshots, tick-by-tick volatility
+
+**Use cases**:
+- Immediate execution decisions
+- Stop-loss triggers
+- Real-time P&L tracking
+
+**Example keys**:
+- `current_position_{stock_code}`: Current holdings
+- `live_price_{stock_code}`: Latest quote
+- `volatility_5m_{stock_code}`: 5-minute rolling volatility
+
+### L6: Daily
+**Retention**: 90 days
+**Timeframe format**: `YYYY-MM-DD`
+**Content**: Daily trade logs, end-of-day P&L, market summaries, decision accuracy
+
+**Use cases**:
+- Daily performance review
+- Identify patterns in recent trading
+- Backtest strategy adjustments
+
+**Example keys**:
+- `total_pnl`: Daily profit/loss
+- `trade_count`: Number of trades
+- `win_rate`: Percentage of profitable trades
+- `avg_confidence`: Average Gemini confidence
+
+### L5: Weekly
+**Retention**: 1 year
+**Timeframe format**: `YYYY-Www` (ISO week, e.g., `2026-W06`)
+**Content**: Weekly stock selection, sector rotation, volatility regime classification
+
+**Use cases**:
+- Weekly strategy adjustment
+- Sector momentum tracking
+- Identify hot/cold markets
+
+**Example keys**:
+- `weekly_pnl`: Week's total P&L
+- `top_performers`: Best-performing stocks
+- `sector_focus`: Dominant sectors
+- `avg_confidence`: Weekly average confidence
+
+### L4: Monthly
+**Retention**: 2 years
+**Timeframe format**: `YYYY-MM`
+**Content**: Monthly portfolio rebalancing, risk exposure analysis, drawdown recovery
+
+**Use cases**:
+- Monthly performance reporting
+- Risk exposure adjustment
+- Correlation analysis
+
+**Example keys**:
+- `monthly_pnl`: Month's total P&L
+- `sharpe_ratio`: Risk-adjusted return
+- `max_drawdown`: Largest peak-to-trough decline
+- `rebalancing_notes`: Manual insights
+
+### L3: Quarterly
+**Retention**: 3 years
+**Timeframe format**: `YYYY-Qn` (e.g., `2026-Q1`)
+**Content**: Quarterly strategy pivots, market phase detection (bull/bear/sideways), macro regime changes
+
+**Use cases**:
+- Strategic pivots (e.g., growth → value)
+- Macro regime classification
+- Long-term pattern recognition
+
+**Example keys**:
+- `quarterly_pnl`: Quarter's total P&L
+- `market_phase`: Bull/Bear/Sideways
+- `strategy_adjustments`: Major changes made
+- `lessons_learned`: Key insights
+
+### L2: Annual
+**Retention**: 10 years
+**Timeframe format**: `YYYY`
+**Content**: Yearly returns, Sharpe ratio, max drawdown, win rate, strategy effectiveness
+
+**Use cases**:
+- Annual performance review
+- Multi-year trend analysis
+- Strategy benchmarking
+
+**Example keys**:
+- `annual_pnl`: Year's total P&L
+- `sharpe_ratio`: Annual risk-adjusted return
+- `win_rate`: Yearly win percentage
+- `best_strategy`: Most successful strategy
+- `worst_mistake`: Biggest lesson learned
+
+### L1: Legacy
+**Retention**: Forever
+**Timeframe format**: `LEGACY` (single timeframe)
+**Content**: Cumulative trading history, core principles, generational wisdom
+
+**Use cases**:
+- Long-term philosophy
+- Foundational rules
+- Lessons that transcend market cycles
+
+**Example keys**:
+- `total_pnl`: All-time profit/loss
+- `years_traded`: Trading longevity
+- `avg_annual_pnl`: Long-term average return
+- `core_principles`: Immutable trading rules
+- `greatest_trades`: Hall of fame
+- `never_again`: Permanent warnings
+
+## Usage
+
+### Setting Context
+
+```python
+from src.context import ContextLayer, ContextStore
+from src.db import init_db
+
+conn = init_db("data/ouroboros.db")
+store = ContextStore(conn)
+
+# Store daily P&L
+store.set_context(
+    layer=ContextLayer.L6_DAILY,
+    timeframe="2026-02-04",
+    key="total_pnl",
+    value=1234.56
+)
+
+# Store weekly insight
+store.set_context(
+    layer=ContextLayer.L5_WEEKLY,
+    timeframe="2026-W06",
+    key="top_performers",
+    value=["005930", "000660", "035720"]  # JSON-serializable
+)
+
+# Store legacy wisdom
+store.set_context(
+    layer=ContextLayer.L1_LEGACY,
+    timeframe="LEGACY",
+    key="core_principles",
+    value=[
+        "Cut losses fast",
+        "Let winners run",
+        "Never average down on losing positions"
+    ]
+)
+```
+
+### Retrieving Context
+
+```python
+# Get a specific value
+pnl = store.get_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl")
+# Returns: 1234.56
+
+# Get all keys for a timeframe
+daily_summary = store.get_all_contexts(ContextLayer.L6_DAILY, "2026-02-04")
+# Returns: {"total_pnl": 1234.56, "trade_count": 10, "win_rate": 60.0, ...}
+
+# Get all data for a layer (any timeframe)
+all_daily = store.get_all_contexts(ContextLayer.L6_DAILY)
+# Returns: {"total_pnl": 1234.56, "trade_count": 10, ...} (latest timeframes first)
+
+# Get the latest timeframe
+latest = store.get_latest_timeframe(ContextLayer.L6_DAILY)
+# Returns: "2026-02-04"
+```
+
+### Automatic Aggregation
+
+The `ContextAggregator` rolls up data from lower to higher layers:
+
+```python
+from src.context.aggregator import ContextAggregator
+
+aggregator = ContextAggregator(conn)
+
+# Aggregate daily metrics from trades
+aggregator.aggregate_daily_from_trades("2026-02-04")
+
+# Roll up weekly from daily
+aggregator.aggregate_weekly_from_daily("2026-W06")
+
+# Roll up all layers at once (bottom-up)
+aggregator.run_all_aggregations()
+```
+
+**Aggregation schedule** (recommended):
+- **L7 → L6**: Every midnight (daily rollup)
+- **L6 → L5**: Every Sunday (weekly rollup)
+- **L5 → L4**: First day of each month (monthly rollup)
+- **L4 → L3**: First day of quarter (quarterly rollup)
+- **L3 → L2**: January 1st (annual rollup)
+- **L2 → L1**: On demand (major milestones)
+
+### Context Cleanup
+
+Expired contexts are automatically deleted based on retention policies:
+
+```python
+# Manual cleanup
+deleted = store.cleanup_expired_contexts()
+# Returns: {ContextLayer.L7_REALTIME: 42, ContextLayer.L6_DAILY: 15, ...}
+```
+
+**Retention policies** (defined in `src/context/layer.py`):
+- L1: Forever
+- L2: 10 years
+- L3: 3 years
+- L4: 2 years
+- L5: 1 year
+- L6: 90 days
+- L7: 7 days
+
+## Integration with Gemini Brain
+
+The context tree provides hierarchical memory for decision-making:
+
+```python
+from src.brain.gemini_client import GeminiClient
+
+# Build prompt with multi-layer context
+def build_enhanced_prompt(stock_code: str, store: ContextStore) -> str:
+    # L7: Real-time data
+    current_price = store.get_context(ContextLayer.L7_REALTIME, "2026-02-04", f"live_price_{stock_code}")
+
+    # L6: Recent daily performance
+    yesterday_pnl = store.get_context(ContextLayer.L6_DAILY, "2026-02-03", "total_pnl")
+
+    # L5: Weekly trend
+    weekly_data = store.get_all_contexts(ContextLayer.L5_WEEKLY, "2026-W06")
+
+    # L1: Core principles
+    principles = store.get_context(ContextLayer.L1_LEGACY, "LEGACY", "core_principles")
+
+    return f"""
+    Analyze {stock_code} for trading decision.
+
+    Current price: {current_price}
+    Yesterday's P&L: {yesterday_pnl}
+    This week: {weekly_data}
+
+    Core principles:
+    {chr(10).join(f'- {p}' for p in principles)}
+
+    Decision (BUY/SELL/HOLD):
+    """
+```
+
+## Database Schema
+
+```sql
+-- Context storage
+CREATE TABLE contexts (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    layer TEXT NOT NULL,          -- L1_LEGACY, L2_ANNUAL, ..., L7_REALTIME
+    timeframe TEXT NOT NULL,      -- "LEGACY", "2026", "2026-Q1", "2026-02", "2026-W06", "2026-02-04"
+    key TEXT NOT NULL,            -- "total_pnl", "win_rate", "core_principles", etc.
+    value TEXT NOT NULL,          -- JSON-serialized value
+    created_at TEXT NOT NULL,     -- ISO 8601 timestamp
+    updated_at TEXT NOT NULL,     -- ISO 8601 timestamp
+    UNIQUE(layer, timeframe, key)
+);
+
+-- Layer metadata
+CREATE TABLE context_metadata (
+    layer TEXT PRIMARY KEY,
+    description TEXT NOT NULL,
+    retention_days INTEGER,       -- NULL = keep forever
+    aggregation_source TEXT       -- Parent layer for rollup
+);
+
+-- Indices for fast queries
+CREATE INDEX idx_contexts_layer ON contexts(layer);
+CREATE INDEX idx_contexts_timeframe ON contexts(timeframe);
+CREATE INDEX idx_contexts_updated ON contexts(updated_at);
+```
+
+## Best Practices
+
+1. **Write to leaf layers only** — Never manually write to L1-L5; let aggregation populate them
+2. **Aggregate regularly** — Schedule aggregation jobs to keep higher layers fresh
+3. **Query specific timeframes** — Use `get_context(layer, timeframe, key)` for precise retrieval
+4. **Clean up periodically** — Run `cleanup_expired_contexts()` weekly to free space
+5. **Preserve L1 forever** — Legacy wisdom should never expire
+6. **Use JSON-serializable values** — Store dicts, lists, strings, numbers (not custom objects)
+
+## Testing
+
+See `tests/test_context.py` for comprehensive test coverage (18 tests, 100% coverage on context modules).
+
+```bash
+pytest tests/test_context.py -v
+```
+
+## References
+
+- **Implementation**: `src/context/`
+  - `layer.py`: Layer definitions and metadata
+  - `store.py`: CRUD operations
+  - `aggregator.py`: Bottom-up aggregation logic
+- **Database**: `src/db.py` (table initialization)
+- **Tests**: `tests/test_context.py`
+- **Related**: Pillar 2 (Multi-layered Context Management)

docs/testing.md

@@ -0,0 +1,213 @@
+# Testing Guidelines
+
+## Test Structure
+
+**54 tests** across four files. `asyncio_mode = "auto"` in pyproject.toml — async tests need no special decorator.
+
+The `settings` fixture in `conftest.py` provides safe defaults with test credentials and in-memory DB.
+
+### Test Files
+
+#### `tests/test_risk.py` (11 tests)
+- Circuit breaker boundaries
+- Fat-finger edge cases
+- P&L calculation edge cases
+- Order validation logic
+
+**Example:**
+```python
+def test_circuit_breaker_exact_threshold(risk_manager):
+    """Circuit breaker should trip at exactly -3.0%."""
+    with pytest.raises(CircuitBreakerTripped):
+        risk_manager.validate_order(
+            current_pnl_pct=-3.0,
+            order_amount=1000,
+            total_cash=10000
+        )
+```
+
+#### `tests/test_broker.py` (6 tests)
+- OAuth token lifecycle
+- Rate limiting enforcement
+- Hash key generation
+- Network error handling
+- SSL context configuration
+
+**Example:**
+```python
+async def test_rate_limiter(broker):
+    """Rate limiter should delay requests to stay under 10 RPS."""
+    start = time.monotonic()
+    for _ in range(15):  # 15 requests
+        await broker._rate_limiter.acquire()
+    elapsed = time.monotonic() - start
+    assert elapsed >= 1.0  # Should take at least 1 second
+```
+
+#### `tests/test_brain.py` (18 tests)
+- Valid JSON parsing
+- Markdown-wrapped JSON handling
+- Malformed JSON fallback
+- Missing fields handling
+- Invalid action validation
+- Confidence threshold enforcement
+- Empty response handling
+- Prompt construction for different markets
+
+**Example:**
+```python
+async def test_confidence_below_threshold_forces_hold(brain):
+    """Decisions below confidence threshold should force HOLD."""
+    decision = brain.parse_response('{"action":"BUY","confidence":70,"rationale":"test"}')
+    assert decision.action == "HOLD"
+    assert decision.confidence == 70
+```
+
+#### `tests/test_market_schedule.py` (19 tests)
+- Market open/close logic
+- Timezone handling (UTC, Asia/Seoul, America/New_York, etc.)
+- DST (Daylight Saving Time) transitions
+- Weekend handling
+- Lunch break logic
+- Multiple market filtering
+- Next market open calculation
+
+**Example:**
+```python
+def test_is_market_open_during_trading_hours():
+    """Market should be open during regular trading hours."""
+    # KRX: 9:00-15:30 KST, no lunch break
+    market = MARKETS["KR"]
+    trading_time = datetime(2026, 2, 3, 10, 0, tzinfo=ZoneInfo("Asia/Seoul"))  # Monday 10:00
+    assert is_market_open(market, trading_time) is True
+```
+
+## Coverage Requirements
+
+**Minimum coverage: 80%**
+
+Check coverage:
+```bash
+pytest -v --cov=src --cov-report=term-missing
+```
+
+Expected output:
+```
+Name                          Stmts   Miss  Cover   Missing
+-----------------------------------------------------------
+src/brain/gemini_client.py       85      5    94%   165-169
+src/broker/kis_api.py           120     12    90%   ...
+src/core/risk_manager.py         35      2    94%   ...
+src/db.py                        25      1    96%   ...
+src/main.py                     150     80    47%   (excluded from CI)
+src/markets/schedule.py          95      3    97%   ...
+-----------------------------------------------------------
+TOTAL                           510     103   80%
+```
+
+**Note:** `main.py` has lower coverage as it contains the main loop which is tested via integration/manual testing.
+
+## Test Configuration
+
+### `pyproject.toml`
+```toml
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+testpaths = ["tests"]
+python_files = ["test_*.py"]
+```
+
+### `tests/conftest.py`
+```python
+@pytest.fixture
+def settings() -> Settings:
+    """Provide test settings with safe defaults."""
+    return Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+        MODE="paper",
+        DB_PATH=":memory:",  # In-memory SQLite
+        CONFIDENCE_THRESHOLD=80,
+        ENABLED_MARKETS="KR",
+    )
+```
+
+## Writing New Tests
+
+### Naming Convention
+- Test files: `test_<module>.py`
+- Test functions: `test_<feature>_<scenario>()`
+- Use descriptive names that explain what is being tested
+
+### Good Test Example
+```python
+async def test_send_order_with_market_price(broker, settings):
+    """Market orders should use price=0 and ORD_DVSN='01'."""
+    # Arrange
+    stock_code = "005930"
+    order_type = "BUY"
+    quantity = 10
+
+    # Act
+    with patch.object(broker._session, 'post') as mock_post:
+        mock_post.return_value.__aenter__.return_value.status = 200
+        mock_post.return_value.__aenter__.return_value.json = AsyncMock(
+            return_value={"rt_cd": "0", "msg1": "OK"}
+        )
+
+        await broker.send_order(stock_code, order_type, quantity, price=0)
+
+    # Assert
+    call_args = mock_post.call_args
+    body = call_args.kwargs['json']
+    assert body['ORD_DVSN'] == '01'  # Market order
+    assert body['ORD_UNPR'] == '0'   # Price 0
+```
+
+### Test Checklist
+- [ ] Test passes in isolation (`pytest tests/test_foo.py::test_bar -v`)
+- [ ] Test has clear docstring explaining what it tests
+- [ ] Arrange-Act-Assert structure
+- [ ] Uses appropriate fixtures from conftest.py
+- [ ] Mocks external dependencies (API calls, network)
+- [ ] Tests edge cases and error conditions
+- [ ] Doesn't rely on test execution order
+
+## Running Tests
+
+```bash
+# All tests
+pytest -v
+
+# Specific file
+pytest tests/test_risk.py -v
+
+# Specific test
+pytest tests/test_brain.py::test_parse_valid_json -v
+
+# With coverage
+pytest -v --cov=src --cov-report=term-missing
+
+# Stop on first failure
+pytest -x
+
+# Verbose output with print statements
+pytest -v -s
+```
+
+## CI/CD Integration
+
+Tests run automatically on:
+- Every commit to feature branches
+- Every PR to main
+- Scheduled daily runs
+
+**Blocking conditions:**
+- Test failures → PR blocked
+- Coverage < 80% → PR blocked (warning only for main.py)
+
+**Non-blocking:**
+- `mypy --strict` errors (type hints encouraged but not enforced)
+- `ruff check` warnings (must be acknowledged)

docs/workflow.md

@@ -0,0 +1,75 @@
+# Development Workflow
+
+## Git Workflow Policy
+
+**CRITICAL: All code changes MUST follow this workflow. Direct pushes to `main` are ABSOLUTELY PROHIBITED.**
+
+1. **Create Gitea Issue First** — All features, bug fixes, and policy changes require a Gitea issue before any code is written
+2. **Create Feature Branch** — Branch from `main` using format `feature/issue-{N}-{short-description}`
+3. **Implement Changes** — Write code, tests, and documentation on the feature branch
+4. **Create Pull Request** — Submit PR to `main` branch referencing the issue number
+5. **Review & Merge** — After approval, merge via PR (squash or merge commit)
+
+**Never commit directly to `main`.** This policy applies to all changes, no exceptions.
+
+## Agent Workflow
+
+**Modern AI development leverages specialized agents for concurrent, efficient task execution.**
+
+### Parallel Execution Strategy
+
+Use **git worktree** or **subagents** (via the Task tool) to handle multiple requirements simultaneously:
+
+- Each task runs in independent context
+- Parallel branches for concurrent features
+- Isolated test environments prevent interference
+- Faster iteration with distributed workload
+
+### Specialized Agent Roles
+
+Deploy task-specific agents as needed instead of handling everything in the main conversation:
+
+- **Conversational Agent** (main) — Interface with user, coordinate other agents
+- **Ticket Management Agent** — Create/update Gitea issues, track task status
+- **Design Agent** — Architectural planning, RFC documents, API design
+- **Code Writing Agent** — Implementation following specs
+- **Testing Agent** — Write tests, verify coverage, run test suites
+- **Documentation Agent** — Update docs, docstrings, CLAUDE.md, README
+- **Review Agent** — Code review, lint checks, security audits
+- **Custom Agents** — Created dynamically for specialized tasks (performance analysis, migration scripts, etc.)
+
+### When to Use Agents
+
+**Prefer spawning specialized agents for:**
+
+1. Complex multi-file changes requiring exploration
+2. Tasks with clear, isolated scope (e.g., "write tests for module X")
+3. Parallel work streams (feature A + bugfix B simultaneously)
+4. Long-running analysis (codebase search, dependency audit)
+5. Tasks requiring different contexts (multiple git worktrees)
+
+**Use the main conversation for:**
+
+1. User interaction and clarification
+2. Quick single-file edits
+3. Coordinating agent work
+4. High-level decision making
+
+### Implementation
+
+```python
+# Example: Spawn parallel test and documentation agents
+task_tool(
+    subagent_type="general-purpose",
+    prompt="Write comprehensive tests for src/markets/schedule.py",
+    description="Write schedule tests"
+)
+
+task_tool(
+    subagent_type="general-purpose",
+    prompt="Update README.md with global market feature documentation",
+    description="Update README"
+)
+```
+
+Use `run_in_background=True` for independent tasks that don't block subsequent work.

pyproject.toml

@@ -8,6 +8,7 @@ dependencies = [
     "pydantic>=2.5,<3",
     "pydantic-settings>=2.1,<3",
     "google-genai>=1.0,<2",
+    "scipy>=1.11,<2",
 ]
 
 [project.optional-dependencies]

src/analysis/__init__.py

@@ -0,0 +1,8 @@
+"""Technical analysis and market scanning modules."""
+
+from __future__ import annotations
+
+from src.analysis.scanner import MarketScanner
+from src.analysis.volatility import VolatilityAnalyzer
+
+__all__ = ["VolatilityAnalyzer", "MarketScanner"]

src/analysis/scanner.py

@@ -0,0 +1,237 @@
+"""Real-time market scanner for detecting high-momentum stocks.
+
+Scans all available stocks in a market and ranks by volatility/momentum score.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import logging
+from dataclasses import dataclass
+from typing import Any
+
+from src.analysis.volatility import VolatilityAnalyzer, VolatilityMetrics
+from src.broker.kis_api import KISBroker
+from src.broker.overseas import OverseasBroker
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+from src.markets.schedule import MarketInfo
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class ScanResult:
+    """Result from a market scan."""
+
+    market_code: str
+    timestamp: str
+    total_scanned: int
+    top_movers: list[VolatilityMetrics]
+    breakouts: list[str]  # Stock codes with breakout patterns
+    breakdowns: list[str]  # Stock codes with breakdown patterns
+
+
+class MarketScanner:
+    """Scans markets for high-volatility, high-momentum stocks."""
+
+    def __init__(
+        self,
+        broker: KISBroker,
+        overseas_broker: OverseasBroker,
+        volatility_analyzer: VolatilityAnalyzer,
+        context_store: ContextStore,
+        top_n: int = 5,
+    ) -> None:
+        """Initialize the market scanner.
+
+        Args:
+            broker: KIS broker instance for domestic market
+            overseas_broker: Overseas broker instance
+            volatility_analyzer: Volatility analyzer instance
+            context_store: Context store for L7 real-time data
+            top_n: Number of top movers to return per market (default 5)
+        """
+        self.broker = broker
+        self.overseas_broker = overseas_broker
+        self.analyzer = volatility_analyzer
+        self.context_store = context_store
+        self.top_n = top_n
+
+    async def scan_stock(
+        self,
+        stock_code: str,
+        market: MarketInfo,
+    ) -> VolatilityMetrics | None:
+        """Scan a single stock for volatility metrics.
+
+        Args:
+            stock_code: Stock code to scan
+            market: Market information
+
+        Returns:
+            VolatilityMetrics if successful, None on error
+        """
+        try:
+            if market.is_domestic:
+                orderbook = await self.broker.get_orderbook(stock_code)
+            else:
+                # For overseas, we need to adapt the price data structure
+                price_data = await self.overseas_broker.get_overseas_price(
+                    market.exchange_code, stock_code
+                )
+                # Convert to orderbook-like structure
+                orderbook = {
+                    "output1": {
+                        "stck_prpr": price_data.get("output", {}).get("last", "0"),
+                        "acml_vol": price_data.get("output", {}).get("tvol", "0"),
+                    }
+                }
+
+            # For now, use empty price history (would need real historical data)
+            # In production, this would fetch from a time-series database or API
+            price_history: dict[str, Any] = {
+                "high": [],
+                "low": [],
+                "close": [],
+                "volume": [],
+            }
+
+            metrics = self.analyzer.analyze(stock_code, orderbook, price_history)
+
+            # Store in L7 real-time layer
+            from datetime import UTC, datetime
+            timeframe = datetime.now(UTC).isoformat()
+            self.context_store.set_context(
+                ContextLayer.L7_REALTIME,
+                timeframe,
+                f"{market.code}_{stock_code}_volatility",
+                {
+                    "price": metrics.current_price,
+                    "atr": metrics.atr,
+                    "price_change_1m": metrics.price_change_1m,
+                    "volume_surge": metrics.volume_surge,
+                    "momentum_score": metrics.momentum_score,
+                },
+            )
+
+            return metrics
+
+        except Exception as exc:
+            logger.warning("Failed to scan %s (%s): %s", stock_code, market.code, exc)
+            return None
+
+    async def scan_market(
+        self,
+        market: MarketInfo,
+        stock_codes: list[str],
+    ) -> ScanResult:
+        """Scan all stocks in a market and rank by momentum.
+
+        Args:
+            market: Market to scan
+            stock_codes: List of stock codes to scan
+
+        Returns:
+            ScanResult with ranked stocks
+        """
+        from datetime import UTC, datetime
+
+        logger.info("Scanning %s market (%d stocks)", market.name, len(stock_codes))
+
+        # Scan all stocks concurrently (with rate limiting handled by broker)
+        tasks = [self.scan_stock(code, market) for code in stock_codes]
+        results = await asyncio.gather(*tasks)
+
+        # Filter out failures and sort by momentum score
+        valid_metrics = [m for m in results if m is not None]
+        valid_metrics.sort(key=lambda m: m.momentum_score, reverse=True)
+
+        # Get top N movers
+        top_movers = valid_metrics[: self.top_n]
+
+        # Detect breakouts and breakdowns
+        breakouts = [
+            m.stock_code for m in valid_metrics if self.analyzer.is_breakout(m)
+        ]
+        breakdowns = [
+            m.stock_code for m in valid_metrics if self.analyzer.is_breakdown(m)
+        ]
+
+        logger.info(
+            "%s scan complete: %d scanned, top momentum=%.1f, %d breakouts, %d breakdowns",
+            market.name,
+            len(valid_metrics),
+            top_movers[0].momentum_score if top_movers else 0.0,
+            len(breakouts),
+            len(breakdowns),
+        )
+
+        # Store scan results in L7
+        timeframe = datetime.now(UTC).isoformat()
+        self.context_store.set_context(
+            ContextLayer.L7_REALTIME,
+            timeframe,
+            f"{market.code}_scan_result",
+            {
+                "total_scanned": len(valid_metrics),
+                "top_movers": [m.stock_code for m in top_movers],
+                "breakouts": breakouts,
+                "breakdowns": breakdowns,
+            },
+        )
+
+        return ScanResult(
+            market_code=market.code,
+            timestamp=timeframe,
+            total_scanned=len(valid_metrics),
+            top_movers=top_movers,
+            breakouts=breakouts,
+            breakdowns=breakdowns,
+        )
+
+    def get_updated_watchlist(
+        self,
+        current_watchlist: list[str],
+        scan_result: ScanResult,
+        max_replacements: int = 2,
+    ) -> list[str]:
+        """Update watchlist by replacing laggards with leaders.
+
+        Args:
+            current_watchlist: Current watchlist
+            scan_result: Recent scan result
+            max_replacements: Maximum stocks to replace per scan
+
+        Returns:
+            Updated watchlist with leaders
+        """
+        # Keep stocks that are in top movers
+        top_codes = [m.stock_code for m in scan_result.top_movers]
+        keepers = [code for code in current_watchlist if code in top_codes]
+
+        # Add new leaders not in current watchlist
+        new_leaders = [code for code in top_codes if code not in current_watchlist]
+
+        # Limit replacements
+        new_leaders = new_leaders[:max_replacements]
+
+        # Create updated watchlist
+        updated = keepers + new_leaders
+
+        # If we removed too many, backfill from current watchlist
+        if len(updated) < len(current_watchlist):
+            backfill = [
+                code for code in current_watchlist
+                if code not in updated
+            ][: len(current_watchlist) - len(updated)]
+            updated.extend(backfill)
+
+        logger.info(
+            "Watchlist updated: %d kept, %d new leaders, %d total",
+            len(keepers),
+            len(new_leaders),
+            len(updated),
+        )
+
+        return updated

src/analysis/volatility.py

@@ -0,0 +1,325 @@
+"""Volatility and momentum analysis for stock selection.
+
+Calculates ATR, price change percentages, volume surges, and price-volume divergence.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Any
+
+
+@dataclass
+class VolatilityMetrics:
+    """Volatility and momentum metrics for a stock."""
+
+    stock_code: str
+    current_price: float
+    atr: float  # Average True Range (14 periods)
+    price_change_1m: float  # 1-minute price change %
+    price_change_5m: float  # 5-minute price change %
+    price_change_15m: float  # 15-minute price change %
+    volume_surge: float  # Volume vs average (ratio)
+    pv_divergence: float  # Price-volume divergence score
+    momentum_score: float  # Combined momentum score (0-100)
+
+    def __repr__(self) -> str:
+        return (
+            f"VolatilityMetrics({self.stock_code}: "
+            f"price={self.current_price:.2f}, "
+            f"atr={self.atr:.2f}, "
+            f"1m={self.price_change_1m:.2f}%, "
+            f"vol_surge={self.volume_surge:.2f}x, "
+            f"momentum={self.momentum_score:.1f})"
+        )
+
+
+class VolatilityAnalyzer:
+    """Analyzes stock volatility and momentum for leader detection."""
+
+    def __init__(self, min_volume_surge: float = 2.0, min_price_change: float = 1.0) -> None:
+        """Initialize the volatility analyzer.
+
+        Args:
+            min_volume_surge: Minimum volume surge ratio (default 2x average)
+            min_price_change: Minimum price change % for breakout (default 1%)
+        """
+        self.min_volume_surge = min_volume_surge
+        self.min_price_change = min_price_change
+
+    def calculate_atr(
+        self,
+        high_prices: list[float],
+        low_prices: list[float],
+        close_prices: list[float],
+        period: int = 14,
+    ) -> float:
+        """Calculate Average True Range (ATR).
+
+        Args:
+            high_prices: List of high prices (most recent last)
+            low_prices: List of low prices (most recent last)
+            close_prices: List of close prices (most recent last)
+            period: ATR period (default 14)
+
+        Returns:
+            ATR value
+        """
+        if (
+            len(high_prices) < period + 1
+            or len(low_prices) < period + 1
+            or len(close_prices) < period + 1
+        ):
+            return 0.0
+
+        true_ranges: list[float] = []
+        for i in range(1, len(high_prices)):
+            high = high_prices[i]
+            low = low_prices[i]
+            prev_close = close_prices[i - 1]
+
+            tr = max(
+                high - low,
+                abs(high - prev_close),
+                abs(low - prev_close),
+            )
+            true_ranges.append(tr)
+
+        if len(true_ranges) < period:
+            return 0.0
+
+        # Simple Moving Average of True Range
+        recent_tr = true_ranges[-period:]
+        return sum(recent_tr) / len(recent_tr)
+
+    def calculate_price_change(
+        self, current_price: float, past_price: float
+    ) -> float:
+        """Calculate price change percentage.
+
+        Args:
+            current_price: Current price
+            past_price: Past price to compare against
+
+        Returns:
+            Price change percentage
+        """
+        if past_price == 0:
+            return 0.0
+        return ((current_price - past_price) / past_price) * 100
+
+    def calculate_volume_surge(
+        self, current_volume: float, avg_volume: float
+    ) -> float:
+        """Calculate volume surge ratio.
+
+        Args:
+            current_volume: Current volume
+            avg_volume: Average volume
+
+        Returns:
+            Volume surge ratio (current / average)
+        """
+        if avg_volume == 0:
+            return 1.0
+        return current_volume / avg_volume
+
+    def calculate_pv_divergence(
+        self,
+        price_change: float,
+        volume_surge: float,
+    ) -> float:
+        """Calculate price-volume divergence score.
+
+        Positive divergence: Price up + Volume up = bullish
+        Negative divergence: Price up + Volume down = bearish
+        Neutral: Price/volume move together moderately
+
+        Args:
+            price_change: Price change percentage
+            volume_surge: Volume surge ratio
+
+        Returns:
+            Divergence score (-100 to +100)
+        """
+        # Normalize volume surge to -1 to +1 scale (1.0 = neutral)
+        volume_signal = (volume_surge - 1.0) * 10  # Scale for sensitivity
+
+        # Calculate divergence
+        # Positive: price and volume move in same direction
+        # Negative: price and volume move in opposite directions
+        if price_change > 0 and volume_surge > 1.0:
+            # Bullish: price up, volume up
+            return min(100.0, price_change * volume_signal)
+        elif price_change < 0 and volume_surge < 1.0:
+            # Bearish confirmation: price down, volume down
+            return max(-100.0, price_change * volume_signal)
+        elif price_change > 0 and volume_surge < 1.0:
+            # Bearish divergence: price up but volume low (weak rally)
+            return -abs(price_change) * 0.5
+        elif price_change < 0 and volume_surge > 1.0:
+            # Selling pressure: price down, volume up
+            return price_change * volume_signal
+        else:
+            return 0.0
+
+    def calculate_momentum_score(
+        self,
+        price_change_1m: float,
+        price_change_5m: float,
+        price_change_15m: float,
+        volume_surge: float,
+        atr: float,
+        current_price: float,
+    ) -> float:
+        """Calculate combined momentum score (0-100).
+
+        Weights:
+        - 1m change: 40%
+        - 5m change: 30%
+        - 15m change: 20%
+        - Volume surge: 10%
+
+        Args:
+            price_change_1m: 1-minute price change %
+            price_change_5m: 5-minute price change %
+            price_change_15m: 15-minute price change %
+            volume_surge: Volume surge ratio
+            atr: Average True Range
+            current_price: Current price
+
+        Returns:
+            Momentum score (0-100)
+        """
+        # Weight recent changes more heavily
+        weighted_change = (
+            price_change_1m * 0.4 +
+            price_change_5m * 0.3 +
+            price_change_15m * 0.2
+        )
+
+        # Volume contribution (normalized to 0-10 scale)
+        volume_contribution = min(10.0, (volume_surge - 1.0) * 5.0)
+
+        # Volatility bonus: higher ATR = higher potential (normalized)
+        volatility_bonus = 0.0
+        if current_price > 0:
+            atr_pct = (atr / current_price) * 100
+            volatility_bonus = min(10.0, atr_pct)
+
+        # Combine scores
+        raw_score = weighted_change + volume_contribution + volatility_bonus
+
+        # Normalize to 0-100 scale
+        # Assume typical momentum range is -10 to +30
+        normalized = ((raw_score + 10) / 40) * 100
+
+        return max(0.0, min(100.0, normalized))
+
+    def analyze(
+        self,
+        stock_code: str,
+        orderbook_data: dict[str, Any],
+        price_history: dict[str, Any],
+    ) -> VolatilityMetrics:
+        """Analyze volatility and momentum for a stock.
+
+        Args:
+            stock_code: Stock code
+            orderbook_data: Current orderbook/quote data
+            price_history: Historical price and volume data
+
+        Returns:
+            VolatilityMetrics with calculated indicators
+        """
+        # Extract current data from orderbook
+        output1 = orderbook_data.get("output1", {})
+        current_price = float(output1.get("stck_prpr", 0))
+        current_volume = float(output1.get("acml_vol", 0))
+
+        # Extract historical data
+        high_prices = price_history.get("high", [])
+        low_prices = price_history.get("low", [])
+        close_prices = price_history.get("close", [])
+        volumes = price_history.get("volume", [])
+
+        # Calculate ATR
+        atr = self.calculate_atr(high_prices, low_prices, close_prices)
+
+        # Calculate price changes (use historical data if available)
+        price_change_1m = 0.0
+        price_change_5m = 0.0
+        price_change_15m = 0.0
+
+        if len(close_prices) > 0:
+            if len(close_prices) >= 1:
+                price_change_1m = self.calculate_price_change(
+                    current_price, close_prices[-1]
+                )
+            if len(close_prices) >= 5:
+                price_change_5m = self.calculate_price_change(
+                    current_price, close_prices[-5]
+                )
+            if len(close_prices) >= 15:
+                price_change_15m = self.calculate_price_change(
+                    current_price, close_prices[-15]
+                )
+
+        # Calculate volume surge
+        avg_volume = sum(volumes) / len(volumes) if volumes else current_volume
+        volume_surge = self.calculate_volume_surge(current_volume, avg_volume)
+
+        # Calculate price-volume divergence
+        pv_divergence = self.calculate_pv_divergence(price_change_1m, volume_surge)
+
+        # Calculate momentum score
+        momentum_score = self.calculate_momentum_score(
+            price_change_1m,
+            price_change_5m,
+            price_change_15m,
+            volume_surge,
+            atr,
+            current_price,
+        )
+
+        return VolatilityMetrics(
+            stock_code=stock_code,
+            current_price=current_price,
+            atr=atr,
+            price_change_1m=price_change_1m,
+            price_change_5m=price_change_5m,
+            price_change_15m=price_change_15m,
+            volume_surge=volume_surge,
+            pv_divergence=pv_divergence,
+            momentum_score=momentum_score,
+        )
+
+    def is_breakout(self, metrics: VolatilityMetrics) -> bool:
+        """Determine if a stock is experiencing a breakout.
+
+        Args:
+            metrics: Volatility metrics for the stock
+
+        Returns:
+            True if breakout conditions are met
+        """
+        return (
+            metrics.price_change_1m >= self.min_price_change
+            and metrics.volume_surge >= self.min_volume_surge
+            and metrics.pv_divergence > 0  # Bullish divergence
+        )
+
+    def is_breakdown(self, metrics: VolatilityMetrics) -> bool:
+        """Determine if a stock is experiencing a breakdown.
+
+        Args:
+            metrics: Volatility metrics for the stock
+
+        Returns:
+            True if breakdown conditions are met
+        """
+        return (
+            metrics.price_change_1m <= -self.min_price_change
+            and metrics.volume_surge >= self.min_volume_surge
+            and metrics.pv_divergence < 0  # Bearish divergence
+        )

src/brain/cache.py

@@ -0,0 +1,293 @@
+"""Response caching system for reducing redundant LLM calls.
+
+This module provides caching for common trading scenarios:
+- TTL-based cache invalidation
+- Cache key based on market conditions
+- Cache hit rate monitoring
+- Special handling for HOLD decisions in quiet markets
+"""
+
+from __future__ import annotations
+
+import hashlib
+import json
+import logging
+import time
+from dataclasses import dataclass
+from typing import TYPE_CHECKING, Any
+
+if TYPE_CHECKING:
+    from src.brain.gemini_client import TradeDecision
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class CacheEntry:
+    """Cached decision with metadata."""
+
+    decision: TradeDecision
+    cached_at: float  # Unix timestamp
+    hit_count: int = 0
+    market_data_hash: str = ""
+
+
+@dataclass
+class CacheMetrics:
+    """Metrics for cache performance monitoring."""
+
+    total_requests: int = 0
+    cache_hits: int = 0
+    cache_misses: int = 0
+    evictions: int = 0
+    total_entries: int = 0
+
+    @property
+    def hit_rate(self) -> float:
+        """Calculate cache hit rate."""
+        if self.total_requests == 0:
+            return 0.0
+        return self.cache_hits / self.total_requests
+
+    def to_dict(self) -> dict[str, Any]:
+        """Convert metrics to dictionary."""
+        return {
+            "total_requests": self.total_requests,
+            "cache_hits": self.cache_hits,
+            "cache_misses": self.cache_misses,
+            "hit_rate": self.hit_rate,
+            "evictions": self.evictions,
+            "total_entries": self.total_entries,
+        }
+
+
+class DecisionCache:
+    """TTL-based cache for trade decisions."""
+
+    def __init__(self, ttl_seconds: int = 300, max_size: int = 1000) -> None:
+        """Initialize the decision cache.
+
+        Args:
+            ttl_seconds: Time-to-live for cache entries in seconds (default: 5 minutes)
+            max_size: Maximum number of cache entries
+        """
+        self.ttl_seconds = ttl_seconds
+        self.max_size = max_size
+        self._cache: dict[str, CacheEntry] = {}
+        self._metrics = CacheMetrics()
+
+    def _generate_cache_key(self, market_data: dict[str, Any]) -> str:
+        """Generate cache key from market data.
+
+        Key is based on:
+        - Stock code
+        - Current price (rounded to reduce sensitivity)
+        - Market conditions (orderbook snapshot)
+
+        Args:
+            market_data: Market data dictionary
+
+        Returns:
+            Cache key string
+        """
+        # Extract key components
+        stock_code = market_data.get("stock_code", "UNKNOWN")
+        current_price = market_data.get("current_price", 0)
+
+        # Round price to reduce sensitivity (cache hits for similar prices)
+        # For prices > 1000, round to nearest 10
+        # For prices < 1000, round to nearest 1
+        if current_price > 1000:
+            price_rounded = round(current_price / 10) * 10
+        else:
+            price_rounded = round(current_price)
+
+        # Include orderbook snapshot (if available)
+        orderbook_key = ""
+        if "orderbook" in market_data and market_data["orderbook"]:
+            ob = market_data["orderbook"]
+            # Just use bid/ask spread as indicator
+            if "bid" in ob and "ask" in ob and ob["bid"] and ob["ask"]:
+                bid_price = ob["bid"][0].get("price", 0) if ob["bid"] else 0
+                ask_price = ob["ask"][0].get("price", 0) if ob["ask"] else 0
+                spread = ask_price - bid_price
+                orderbook_key = f"_spread{spread}"
+
+        # Generate cache key
+        key_str = f"{stock_code}_{price_rounded}{orderbook_key}"
+
+        return key_str
+
+    def _generate_market_hash(self, market_data: dict[str, Any]) -> str:
+        """Generate hash of full market data for invalidation checks.
+
+        Args:
+            market_data: Market data dictionary
+
+        Returns:
+            Hash string
+        """
+        # Create stable JSON representation
+        stable_json = json.dumps(market_data, sort_keys=True, ensure_ascii=False)
+        return hashlib.md5(stable_json.encode()).hexdigest()
+
+    def get(self, market_data: dict[str, Any]) -> TradeDecision | None:
+        """Retrieve cached decision if valid.
+
+        Args:
+            market_data: Market data dictionary
+
+        Returns:
+            Cached TradeDecision if valid, None otherwise
+        """
+        self._metrics.total_requests += 1
+
+        cache_key = self._generate_cache_key(market_data)
+
+        if cache_key not in self._cache:
+            self._metrics.cache_misses += 1
+            return None
+
+        entry = self._cache[cache_key]
+        current_time = time.time()
+
+        # Check TTL
+        if current_time - entry.cached_at > self.ttl_seconds:
+            # Expired
+            del self._cache[cache_key]
+            self._metrics.cache_misses += 1
+            self._metrics.evictions += 1
+            logger.debug("Cache expired for key: %s", cache_key)
+            return None
+
+        # Cache hit
+        entry.hit_count += 1
+        self._metrics.cache_hits += 1
+        logger.debug("Cache hit for key: %s (hits: %d)", cache_key, entry.hit_count)
+
+        return entry.decision
+
+    def set(
+        self,
+        market_data: dict[str, Any],
+        decision: TradeDecision,
+    ) -> None:
+        """Store decision in cache.
+
+        Args:
+            market_data: Market data dictionary
+            decision: TradeDecision to cache
+        """
+        cache_key = self._generate_cache_key(market_data)
+        market_hash = self._generate_market_hash(market_data)
+
+        # Enforce max size (evict oldest if full)
+        if len(self._cache) >= self.max_size:
+            # Find oldest entry
+            oldest_key = min(self._cache.keys(), key=lambda k: self._cache[k].cached_at)
+            del self._cache[oldest_key]
+            self._metrics.evictions += 1
+            logger.debug("Cache full, evicted key: %s", oldest_key)
+
+        # Store entry
+        entry = CacheEntry(
+            decision=decision,
+            cached_at=time.time(),
+            market_data_hash=market_hash,
+        )
+        self._cache[cache_key] = entry
+        self._metrics.total_entries = len(self._cache)
+
+        logger.debug("Cached decision for key: %s", cache_key)
+
+    def invalidate(self, stock_code: str | None = None) -> int:
+        """Invalidate cache entries.
+
+        Args:
+            stock_code: Specific stock code to invalidate, or None for all
+
+        Returns:
+            Number of entries invalidated
+        """
+        if stock_code is None:
+            # Clear all
+            count = len(self._cache)
+            self._cache.clear()
+            self._metrics.evictions += count
+            self._metrics.total_entries = 0
+            logger.info("Invalidated all cache entries (%d)", count)
+            return count
+
+        # Invalidate specific stock
+        keys_to_remove = [k for k in self._cache.keys() if k.startswith(f"{stock_code}_")]
+        count = len(keys_to_remove)
+
+        for key in keys_to_remove:
+            del self._cache[key]
+
+        self._metrics.evictions += count
+        self._metrics.total_entries = len(self._cache)
+        logger.info("Invalidated %d cache entries for stock: %s", count, stock_code)
+
+        return count
+
+    def cleanup_expired(self) -> int:
+        """Remove expired entries from cache.
+
+        Returns:
+            Number of entries removed
+        """
+        current_time = time.time()
+        expired_keys = [
+            k
+            for k, v in self._cache.items()
+            if current_time - v.cached_at > self.ttl_seconds
+        ]
+
+        count = len(expired_keys)
+        for key in expired_keys:
+            del self._cache[key]
+
+        self._metrics.evictions += count
+        self._metrics.total_entries = len(self._cache)
+
+        if count > 0:
+            logger.debug("Cleaned up %d expired cache entries", count)
+
+        return count
+
+    def get_metrics(self) -> CacheMetrics:
+        """Get current cache metrics.
+
+        Returns:
+            CacheMetrics object with current statistics
+        """
+        return self._metrics
+
+    def reset_metrics(self) -> None:
+        """Reset cache metrics."""
+        self._metrics = CacheMetrics(total_entries=len(self._cache))
+        logger.info("Cache metrics reset")
+
+    def should_cache_decision(self, decision: TradeDecision) -> bool:
+        """Determine if a decision should be cached.
+
+        HOLD decisions with low confidence are good candidates for caching,
+        as they're likely to recur in quiet markets.
+
+        Args:
+            decision: TradeDecision to evaluate
+
+        Returns:
+            True if decision should be cached
+        """
+        # Cache HOLD decisions (common in quiet markets)
+        if decision.action == "HOLD":
+            return True
+
+        # Cache high-confidence decisions (stable signals)
+        if decision.confidence >= 90:
+            return True
+
+        # Don't cache low-confidence BUY/SELL (volatile signals)
+        return False

src/brain/context_selector.py

@@ -0,0 +1,296 @@
+"""Smart context selection for optimizing token usage.
+
+This module implements intelligent selection of context layers (L1-L7) based on
+decision type and market conditions:
+- L7 (real-time) for normal trading decisions
+- L6-L5 (daily/weekly) for strategic decisions
+- L4-L1 (monthly/legacy) only for major events or policy changes
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from datetime import UTC, datetime
+from enum import Enum
+from typing import Any
+
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+
+
+class DecisionType(str, Enum):
+    """Type of trading decision being made."""
+
+    NORMAL = "normal"  # Regular trade decision
+    STRATEGIC = "strategic"  # Strategy adjustment
+    MAJOR_EVENT = "major_event"  # Portfolio rebalancing, policy change
+
+
+@dataclass(frozen=True)
+class ContextSelection:
+    """Selected context layers and their relevance scores."""
+
+    layers: list[ContextLayer]
+    relevance_scores: dict[ContextLayer, float]
+    total_score: float
+
+
+class ContextSelector:
+    """Selects optimal context layers to minimize token usage."""
+
+    def __init__(self, store: ContextStore) -> None:
+        """Initialize the context selector.
+
+        Args:
+            store: ContextStore instance for retrieving context data
+        """
+        self.store = store
+
+    def select_layers(
+        self,
+        decision_type: DecisionType = DecisionType.NORMAL,
+        include_realtime: bool = True,
+    ) -> list[ContextLayer]:
+        """Select context layers based on decision type.
+
+        Strategy:
+        - NORMAL: L7 (real-time) only
+        - STRATEGIC: L7 + L6 + L5 (real-time + daily + weekly)
+        - MAJOR_EVENT: All layers L1-L7
+
+        Args:
+            decision_type: Type of decision being made
+            include_realtime: Whether to include L7 real-time data
+
+        Returns:
+            List of context layers to use (ordered by priority)
+        """
+        if decision_type == DecisionType.NORMAL:
+            # Normal trading: only real-time data
+            return [ContextLayer.L7_REALTIME] if include_realtime else []
+
+        elif decision_type == DecisionType.STRATEGIC:
+            # Strategic decisions: real-time + recent history
+            layers = []
+            if include_realtime:
+                layers.append(ContextLayer.L7_REALTIME)
+            layers.extend([ContextLayer.L6_DAILY, ContextLayer.L5_WEEKLY])
+            return layers
+
+        else:  # MAJOR_EVENT
+            # Major events: all layers for comprehensive context
+            layers = []
+            if include_realtime:
+                layers.append(ContextLayer.L7_REALTIME)
+            layers.extend(
+                [
+                    ContextLayer.L6_DAILY,
+                    ContextLayer.L5_WEEKLY,
+                    ContextLayer.L4_MONTHLY,
+                    ContextLayer.L3_QUARTERLY,
+                    ContextLayer.L2_ANNUAL,
+                    ContextLayer.L1_LEGACY,
+                ]
+            )
+            return layers
+
+    def score_layer_relevance(
+        self,
+        layer: ContextLayer,
+        decision_type: DecisionType,
+        current_time: datetime | None = None,
+    ) -> float:
+        """Calculate relevance score for a context layer.
+
+        Relevance is based on:
+        1. Decision type (normal, strategic, major event)
+        2. Layer recency (L7 > L6 > ... > L1)
+        3. Data availability
+
+        Args:
+            layer: Context layer to score
+            decision_type: Type of decision being made
+            current_time: Current time (defaults to now)
+
+        Returns:
+            Relevance score (0.0 to 1.0)
+        """
+        if current_time is None:
+            current_time = datetime.now(UTC)
+
+        # Base scores by decision type
+        base_scores = {
+            DecisionType.NORMAL: {
+                ContextLayer.L7_REALTIME: 1.0,
+                ContextLayer.L6_DAILY: 0.1,
+                ContextLayer.L5_WEEKLY: 0.05,
+                ContextLayer.L4_MONTHLY: 0.01,
+                ContextLayer.L3_QUARTERLY: 0.0,
+                ContextLayer.L2_ANNUAL: 0.0,
+                ContextLayer.L1_LEGACY: 0.0,
+            },
+            DecisionType.STRATEGIC: {
+                ContextLayer.L7_REALTIME: 0.9,
+                ContextLayer.L6_DAILY: 0.8,
+                ContextLayer.L5_WEEKLY: 0.7,
+                ContextLayer.L4_MONTHLY: 0.3,
+                ContextLayer.L3_QUARTERLY: 0.2,
+                ContextLayer.L2_ANNUAL: 0.1,
+                ContextLayer.L1_LEGACY: 0.05,
+            },
+            DecisionType.MAJOR_EVENT: {
+                ContextLayer.L7_REALTIME: 0.7,
+                ContextLayer.L6_DAILY: 0.7,
+                ContextLayer.L5_WEEKLY: 0.7,
+                ContextLayer.L4_MONTHLY: 0.8,
+                ContextLayer.L3_QUARTERLY: 0.8,
+                ContextLayer.L2_ANNUAL: 0.9,
+                ContextLayer.L1_LEGACY: 1.0,
+            },
+        }
+
+        score = base_scores[decision_type].get(layer, 0.0)
+
+        # Check data availability
+        latest_timeframe = self.store.get_latest_timeframe(layer)
+        if latest_timeframe is None:
+            # No data available - reduce score significantly
+            score *= 0.1
+
+        return score
+
+    def select_with_scoring(
+        self,
+        decision_type: DecisionType = DecisionType.NORMAL,
+        min_score: float = 0.5,
+    ) -> ContextSelection:
+        """Select context layers with relevance scoring.
+
+        Args:
+            decision_type: Type of decision being made
+            min_score: Minimum relevance score to include a layer
+
+        Returns:
+            ContextSelection with selected layers and scores
+        """
+        all_layers = [
+            ContextLayer.L7_REALTIME,
+            ContextLayer.L6_DAILY,
+            ContextLayer.L5_WEEKLY,
+            ContextLayer.L4_MONTHLY,
+            ContextLayer.L3_QUARTERLY,
+            ContextLayer.L2_ANNUAL,
+            ContextLayer.L1_LEGACY,
+        ]
+
+        scores = {
+            layer: self.score_layer_relevance(layer, decision_type) for layer in all_layers
+        }
+
+        # Filter by minimum score
+        selected_layers = [layer for layer, score in scores.items() if score >= min_score]
+
+        # Sort by score (descending)
+        selected_layers.sort(key=lambda layer: scores[layer], reverse=True)
+
+        total_score = sum(scores[layer] for layer in selected_layers)
+
+        return ContextSelection(
+            layers=selected_layers,
+            relevance_scores=scores,
+            total_score=total_score,
+        )
+
+    def get_context_data(
+        self,
+        layers: list[ContextLayer],
+        max_items_per_layer: int = 10,
+    ) -> dict[str, Any]:
+        """Retrieve context data for selected layers.
+
+        Args:
+            layers: List of context layers to retrieve
+            max_items_per_layer: Maximum number of items per layer
+
+        Returns:
+            Dictionary with context data organized by layer
+        """
+        result: dict[str, Any] = {}
+
+        for layer in layers:
+            # Get latest timeframe for this layer
+            latest_timeframe = self.store.get_latest_timeframe(layer)
+            if latest_timeframe:
+                # Get all contexts for latest timeframe
+                contexts = self.store.get_all_contexts(layer, latest_timeframe)
+
+                # Limit number of items
+                if len(contexts) > max_items_per_layer:
+                    # Keep only first N items
+                    contexts = dict(list(contexts.items())[:max_items_per_layer])
+
+                result[layer.value] = contexts
+
+        return result
+
+    def estimate_context_tokens(self, context_data: dict[str, Any]) -> int:
+        """Estimate total tokens for context data.
+
+        Args:
+            context_data: Context data dictionary
+
+        Returns:
+            Estimated token count
+        """
+        import json
+
+        from src.brain.prompt_optimizer import PromptOptimizer
+
+        # Serialize to JSON and estimate tokens
+        json_str = json.dumps(context_data, ensure_ascii=False)
+        return PromptOptimizer.estimate_tokens(json_str)
+
+    def optimize_context_for_budget(
+        self,
+        decision_type: DecisionType,
+        max_tokens: int,
+    ) -> dict[str, Any]:
+        """Select and retrieve context data within a token budget.
+
+        Args:
+            decision_type: Type of decision being made
+            max_tokens: Maximum token budget for context
+
+        Returns:
+            Optimized context data within budget
+        """
+        # Start with minimal selection
+        selection = self.select_with_scoring(decision_type, min_score=0.5)
+
+        # Retrieve data
+        context_data = self.get_context_data(selection.layers)
+
+        # Check if within budget
+        estimated_tokens = self.estimate_context_tokens(context_data)
+
+        if estimated_tokens <= max_tokens:
+            return context_data
+
+        # If over budget, progressively reduce
+        # 1. Reduce items per layer
+        for max_items in [5, 3, 1]:
+            context_data = self.get_context_data(selection.layers, max_items)
+            estimated_tokens = self.estimate_context_tokens(context_data)
+            if estimated_tokens <= max_tokens:
+                return context_data
+
+        # 2. Remove lower-priority layers
+        for min_score in [0.6, 0.7, 0.8, 0.9]:
+            selection = self.select_with_scoring(decision_type, min_score=min_score)
+            context_data = self.get_context_data(selection.layers, max_items_per_layer=1)
+            estimated_tokens = self.estimate_context_tokens(context_data)
+            if estimated_tokens <= max_tokens:
+                return context_data
+
+        # Last resort: return only L7 with minimal data
+        return self.get_context_data([ContextLayer.L7_REALTIME], max_items_per_layer=1)

src/brain/gemini_client.py

@@ -2,6 +2,11 @@
 
 Constructs prompts from market data, calls Gemini, and parses structured
 JSON responses into validated TradeDecision objects.
+
+Includes token efficiency optimizations:
+- Prompt compression and abbreviation
+- Response caching for common scenarios
+- Token usage tracking and metrics
 """
 
 from __future__ import annotations
@@ -14,6 +19,8 @@ from typing import Any
 
 from google import genai
 
+from src.brain.cache import DecisionCache
+from src.brain.prompt_optimizer import PromptOptimizer
 from src.config import Settings
 
 logger = logging.getLogger(__name__)
@@ -28,17 +35,35 @@ class TradeDecision:
     action: str  # "BUY" | "SELL" | "HOLD"
     confidence: int  # 0-100
     rationale: str
+    token_count: int = 0  # Estimated tokens used
+    cached: bool = False  # Whether decision came from cache
 
 
 class GeminiClient:
     """Wraps the Gemini API for trade decision-making."""
 
-    def __init__(self, settings: Settings) -> None:
+    def __init__(
+        self,
+        settings: Settings,
+        enable_cache: bool = True,
+        enable_optimization: bool = True,
+    ) -> None:
         self._settings = settings
         self._confidence_threshold = settings.CONFIDENCE_THRESHOLD
         self._client = genai.Client(api_key=settings.GEMINI_API_KEY)
         self._model_name = settings.GEMINI_MODEL
 
+        # Token efficiency features
+        self._enable_cache = enable_cache
+        self._enable_optimization = enable_optimization
+        self._cache = DecisionCache(ttl_seconds=300) if enable_cache else None
+        self._optimizer = PromptOptimizer()
+
+        # Token usage metrics
+        self._total_tokens_used = 0
+        self._total_decisions = 0
+        self._total_cached_decisions = 0
+
     # ------------------------------------------------------------------
     # Prompt Construction
     # ------------------------------------------------------------------
@@ -154,26 +179,141 @@ class GeminiClient:
 
     async def decide(self, market_data: dict[str, Any]) -> TradeDecision:
         """Build prompt, call Gemini, and return a parsed decision."""
-        prompt = self.build_prompt(market_data)
-        logger.info("Requesting trade decision from Gemini")
+        # Check cache first
+        if self._cache:
+            cached_decision = self._cache.get(market_data)
+            if cached_decision:
+                self._total_cached_decisions += 1
+                self._total_decisions += 1
+                logger.info(
+                    "Cache hit for decision",
+                    extra={
+                        "action": cached_decision.action,
+                        "confidence": cached_decision.confidence,
+                        "cache_hit_rate": self.get_cache_hit_rate(),
+                    },
+                )
+                # Return cached decision with cached flag
+                return TradeDecision(
+                    action=cached_decision.action,
+                    confidence=cached_decision.confidence,
+                    rationale=cached_decision.rationale,
+                    token_count=0,
+                    cached=True,
+                )
+
+        # Build optimized prompt
+        if self._enable_optimization:
+            prompt = self._optimizer.build_compressed_prompt(market_data)
+        else:
+            prompt = self.build_prompt(market_data)
+
+        # Estimate tokens
+        token_count = self._optimizer.estimate_tokens(prompt)
+        self._total_tokens_used += token_count
+
+        logger.info(
+            "Requesting trade decision from Gemini",
+            extra={"estimated_tokens": token_count, "optimized": self._enable_optimization},
+        )
 
         try:
             response = await self._client.aio.models.generate_content(
-                model=self._model_name, contents=prompt,
+                model=self._model_name,
+                contents=prompt,
             )
             raw = response.text
         except Exception as exc:
             logger.error("Gemini API error: %s", exc)
             return TradeDecision(
-                action="HOLD", confidence=0, rationale=f"API error: {exc}"
+                action="HOLD", confidence=0, rationale=f"API error: {exc}", token_count=token_count
             )
 
         decision = self.parse_response(raw)
+        self._total_decisions += 1
+
+        # Add token count to decision
+        decision_with_tokens = TradeDecision(
+            action=decision.action,
+            confidence=decision.confidence,
+            rationale=decision.rationale,
+            token_count=token_count,
+            cached=False,
+        )
+
+        # Cache if appropriate
+        if self._cache and self._cache.should_cache_decision(decision):
+            self._cache.set(market_data, decision)
+
         logger.info(
             "Gemini decision",
             extra={
                 "action": decision.action,
                 "confidence": decision.confidence,
+                "tokens": token_count,
+                "avg_tokens": self.get_avg_tokens_per_decision(),
             },
         )
-        return decision
+
+        return decision_with_tokens
+
+    # ------------------------------------------------------------------
+    # Token Efficiency Metrics
+    # ------------------------------------------------------------------
+
+    def get_token_metrics(self) -> dict[str, Any]:
+        """Get token usage metrics.
+
+        Returns:
+            Dictionary with token usage statistics
+        """
+        metrics = {
+            "total_tokens_used": self._total_tokens_used,
+            "total_decisions": self._total_decisions,
+            "total_cached_decisions": self._total_cached_decisions,
+            "avg_tokens_per_decision": self.get_avg_tokens_per_decision(),
+            "cache_hit_rate": self.get_cache_hit_rate(),
+        }
+
+        if self._cache:
+            cache_metrics = self._cache.get_metrics()
+            metrics["cache_metrics"] = cache_metrics.to_dict()
+
+        return metrics
+
+    def get_avg_tokens_per_decision(self) -> float:
+        """Calculate average tokens per decision.
+
+        Returns:
+            Average tokens per decision
+        """
+        if self._total_decisions == 0:
+            return 0.0
+        return self._total_tokens_used / self._total_decisions
+
+    def get_cache_hit_rate(self) -> float:
+        """Calculate cache hit rate.
+
+        Returns:
+            Cache hit rate (0.0 to 1.0)
+        """
+        if self._total_decisions == 0:
+            return 0.0
+        return self._total_cached_decisions / self._total_decisions
+
+    def reset_metrics(self) -> None:
+        """Reset token usage metrics."""
+        self._total_tokens_used = 0
+        self._total_decisions = 0
+        self._total_cached_decisions = 0
+        if self._cache:
+            self._cache.reset_metrics()
+        logger.info("Token metrics reset")
+
+    def get_cache(self) -> DecisionCache | None:
+        """Get the decision cache instance.
+
+        Returns:
+            DecisionCache instance or None if caching disabled
+        """
+        return self._cache

src/brain/prompt_optimizer.py

@@ -0,0 +1,267 @@
+"""Prompt optimization utilities for reducing token usage.
+
+This module provides tools to compress prompts while maintaining decision quality:
+- Token counting
+- Text compression and abbreviation
+- Template-based prompts with variable slots
+- Priority-based context truncation
+"""
+
+from __future__ import annotations
+
+import json
+import re
+from dataclasses import dataclass
+from typing import Any
+
+# Abbreviation mapping for common terms
+ABBREVIATIONS = {
+    "price": "P",
+    "volume": "V",
+    "current": "cur",
+    "previous": "prev",
+    "change": "chg",
+    "percentage": "pct",
+    "market": "mkt",
+    "orderbook": "ob",
+    "foreigner": "fgn",
+    "buy": "B",
+    "sell": "S",
+    "hold": "H",
+    "confidence": "conf",
+    "rationale": "reason",
+    "action": "act",
+    "net": "net",
+}
+
+# Reverse mapping for decompression
+REVERSE_ABBREVIATIONS = {v: k for k, v in ABBREVIATIONS.items()}
+
+
+@dataclass(frozen=True)
+class TokenMetrics:
+    """Metrics about token usage in a prompt."""
+
+    char_count: int
+    word_count: int
+    estimated_tokens: int  # Rough estimate: ~4 chars per token
+    compression_ratio: float = 1.0  # Original / Compressed
+
+
+class PromptOptimizer:
+    """Optimizes prompts to reduce token usage while maintaining quality."""
+
+    @staticmethod
+    def estimate_tokens(text: str) -> int:
+        """Estimate token count for text.
+
+        Uses a simple heuristic: ~4 characters per token for English.
+        This is approximate but sufficient for optimization purposes.
+
+        Args:
+            text: Input text to estimate tokens for
+
+        Returns:
+            Estimated token count
+        """
+        if not text:
+            return 0
+        # Simple estimate: 1 token ≈ 4 characters
+        return max(1, len(text) // 4)
+
+    @staticmethod
+    def count_tokens(text: str) -> TokenMetrics:
+        """Count various metrics for a text.
+
+        Args:
+            text: Input text to analyze
+
+        Returns:
+            TokenMetrics with character, word, and estimated token counts
+        """
+        char_count = len(text)
+        word_count = len(text.split())
+        estimated_tokens = PromptOptimizer.estimate_tokens(text)
+
+        return TokenMetrics(
+            char_count=char_count,
+            word_count=word_count,
+            estimated_tokens=estimated_tokens,
+        )
+
+    @staticmethod
+    def compress_json(data: dict[str, Any]) -> str:
+        """Compress JSON by removing whitespace.
+
+        Args:
+            data: Dictionary to serialize
+
+        Returns:
+            Compact JSON string without whitespace
+        """
+        return json.dumps(data, separators=(",", ":"), ensure_ascii=False)
+
+    @staticmethod
+    def abbreviate_text(text: str, aggressive: bool = False) -> str:
+        """Apply abbreviations to reduce text length.
+
+        Args:
+            text: Input text to abbreviate
+            aggressive: If True, apply more aggressive compression
+
+        Returns:
+            Abbreviated text
+        """
+        result = text
+
+        # Apply word-level abbreviations (case-insensitive)
+        for full, abbr in ABBREVIATIONS.items():
+            # Word boundaries to avoid partial replacements
+            pattern = r"\b" + re.escape(full) + r"\b"
+            result = re.sub(pattern, abbr, result, flags=re.IGNORECASE)
+
+        if aggressive:
+            # Remove articles and filler words
+            result = re.sub(r"\b(a|an|the)\b", "", result, flags=re.IGNORECASE)
+            result = re.sub(r"\b(is|are|was|were)\b", "", result, flags=re.IGNORECASE)
+            # Collapse multiple spaces
+            result = re.sub(r"\s+", " ", result)
+
+        return result.strip()
+
+    @staticmethod
+    def build_compressed_prompt(
+        market_data: dict[str, Any],
+        include_instructions: bool = True,
+        max_length: int | None = None,
+    ) -> str:
+        """Build a compressed prompt from market data.
+
+        Args:
+            market_data: Market data dictionary with stock info
+            include_instructions: Whether to include full instructions
+            max_length: Maximum character length (truncates if needed)
+
+        Returns:
+            Compressed prompt string
+        """
+        # Abbreviated market name
+        market_name = market_data.get("market_name", "KR")
+        if "Korea" in market_name:
+            market_name = "KR"
+        elif "United States" in market_name or "US" in market_name:
+            market_name = "US"
+
+        # Core data - always included
+        core_info = {
+            "mkt": market_name,
+            "code": market_data["stock_code"],
+            "P": market_data["current_price"],
+        }
+
+        # Optional fields
+        if "orderbook" in market_data and market_data["orderbook"]:
+            ob = market_data["orderbook"]
+            # Compress orderbook: keep only top 3 levels
+            compressed_ob = {
+                "bid": ob.get("bid", [])[:3],
+                "ask": ob.get("ask", [])[:3],
+            }
+            core_info["ob"] = compressed_ob
+
+        if market_data.get("foreigner_net", 0) != 0:
+            core_info["fgn_net"] = market_data["foreigner_net"]
+
+        # Compress to JSON
+        data_str = PromptOptimizer.compress_json(core_info)
+
+        if include_instructions:
+            # Minimal instructions
+            prompt = (
+                f"{market_name} trader. Analyze:\n{data_str}\n\n"
+                'Return JSON: {"act":"BUY"|"SELL"|"HOLD","conf":<0-100>,"reason":"<text>"}\n'
+                "Rules: act=BUY/SELL/HOLD, conf=0-100, reason=concise. No markdown."
+            )
+        else:
+            # Data only (for cached contexts where instructions are known)
+            prompt = data_str
+
+        # Truncate if needed
+        if max_length and len(prompt) > max_length:
+            prompt = prompt[:max_length] + "..."
+
+        return prompt
+
+    @staticmethod
+    def truncate_context(
+        context: dict[str, Any],
+        max_tokens: int,
+        priority_keys: list[str] | None = None,
+    ) -> dict[str, Any]:
+        """Truncate context data to fit within token budget.
+
+        Keeps high-priority keys first, then truncates less important data.
+
+        Args:
+            context: Context dictionary to truncate
+            max_tokens: Maximum token budget
+            priority_keys: List of keys to keep (in order of priority)
+
+        Returns:
+            Truncated context dictionary
+        """
+        if not context:
+            return {}
+
+        if priority_keys is None:
+            priority_keys = []
+
+        result: dict[str, Any] = {}
+        current_tokens = 0
+
+        # Add priority keys first
+        for key in priority_keys:
+            if key in context:
+                value_str = json.dumps(context[key])
+                tokens = PromptOptimizer.estimate_tokens(value_str)
+
+                if current_tokens + tokens <= max_tokens:
+                    result[key] = context[key]
+                    current_tokens += tokens
+                else:
+                    break
+
+        # Add remaining keys if space available
+        for key, value in context.items():
+            if key in result:
+                continue
+
+            value_str = json.dumps(value)
+            tokens = PromptOptimizer.estimate_tokens(value_str)
+
+            if current_tokens + tokens <= max_tokens:
+                result[key] = value
+                current_tokens += tokens
+            else:
+                break
+
+        return result
+
+    @staticmethod
+    def calculate_compression_ratio(original: str, compressed: str) -> float:
+        """Calculate compression ratio between original and compressed text.
+
+        Args:
+            original: Original text
+            compressed: Compressed text
+
+        Returns:
+            Compression ratio (original_tokens / compressed_tokens)
+        """
+        original_tokens = PromptOptimizer.estimate_tokens(original)
+        compressed_tokens = PromptOptimizer.estimate_tokens(compressed)
+
+        if compressed_tokens == 0:
+            return 1.0
+
+        return original_tokens / compressed_tokens

src/context/__init__.py

@@ -0,0 +1,10 @@
+"""Multi-layered context management system for trading decisions.
+
+The context tree implements Pillar 2: hierarchical memory management across
+7 time horizons, from real-time quotes to generational wisdom.
+"""
+
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+
+__all__ = ["ContextLayer", "ContextStore"]

src/context/aggregator.py

@@ -0,0 +1,250 @@
+"""Context aggregation logic for rolling up data from lower to higher layers."""
+
+from __future__ import annotations
+
+import sqlite3
+from datetime import UTC, datetime
+from typing import Any
+
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+
+
+class ContextAggregator:
+    """Aggregates context data from lower (finer) to higher (coarser) layers."""
+
+    def __init__(self, conn: sqlite3.Connection) -> None:
+        """Initialize the aggregator with a database connection."""
+        self.conn = conn
+        self.store = ContextStore(conn)
+
+    def aggregate_daily_from_trades(self, date: str | None = None) -> None:
+        """Aggregate L6 (daily) context from trades table.
+
+        Args:
+            date: Date in YYYY-MM-DD format. If None, uses today.
+        """
+        if date is None:
+            date = datetime.now(UTC).date().isoformat()
+
+        # Calculate daily metrics from trades
+        cursor = self.conn.execute(
+            """
+            SELECT
+                COUNT(*) as trade_count,
+                SUM(CASE WHEN action = 'BUY' THEN 1 ELSE 0 END) as buys,
+                SUM(CASE WHEN action = 'SELL' THEN 1 ELSE 0 END) as sells,
+                SUM(CASE WHEN action = 'HOLD' THEN 1 ELSE 0 END) as holds,
+                AVG(confidence) as avg_confidence,
+                SUM(pnl) as total_pnl,
+                COUNT(DISTINCT stock_code) as unique_stocks,
+                SUM(CASE WHEN pnl > 0 THEN 1 ELSE 0 END) as wins,
+                SUM(CASE WHEN pnl < 0 THEN 1 ELSE 0 END) as losses
+            FROM trades
+            WHERE DATE(timestamp) = ?
+            """,
+            (date,),
+        )
+        row = cursor.fetchone()
+
+        if row and row[0] > 0:  # At least one trade
+            trade_count, buys, sells, holds, avg_conf, total_pnl, stocks, wins, losses = row
+
+            # Store daily metrics in L6
+            self.store.set_context(ContextLayer.L6_DAILY, date, "trade_count", trade_count)
+            self.store.set_context(ContextLayer.L6_DAILY, date, "buys", buys)
+            self.store.set_context(ContextLayer.L6_DAILY, date, "sells", sells)
+            self.store.set_context(ContextLayer.L6_DAILY, date, "holds", holds)
+            self.store.set_context(
+                ContextLayer.L6_DAILY, date, "avg_confidence", round(avg_conf, 2)
+            )
+            self.store.set_context(
+                ContextLayer.L6_DAILY, date, "total_pnl", round(total_pnl, 2)
+            )
+            self.store.set_context(ContextLayer.L6_DAILY, date, "unique_stocks", stocks)
+            win_rate = round(wins / max(wins + losses, 1) * 100, 2)
+            self.store.set_context(ContextLayer.L6_DAILY, date, "win_rate", win_rate)
+
+    def aggregate_weekly_from_daily(self, week: str | None = None) -> None:
+        """Aggregate L5 (weekly) context from L6 (daily).
+
+        Args:
+            week: Week in YYYY-Www format (ISO week). If None, uses current week.
+        """
+        if week is None:
+            week = datetime.now(UTC).strftime("%Y-W%V")
+
+        # Get all daily contexts for this week
+        cursor = self.conn.execute(
+            """
+            SELECT key, value FROM contexts
+            WHERE layer = ? AND timeframe LIKE ?
+            """,
+            (ContextLayer.L6_DAILY.value, f"{week[:4]}-%"),  # All days in the year
+        )
+
+        # Group by key and collect all values
+        import json
+        from collections import defaultdict
+
+        daily_data: dict[str, list[Any]] = defaultdict(list)
+        for row in cursor.fetchall():
+            daily_data[row[0]].append(json.loads(row[1]))
+
+        if daily_data:
+            # Sum all PnL values
+            if "total_pnl" in daily_data:
+                total_pnl = sum(daily_data["total_pnl"])
+                self.store.set_context(
+                    ContextLayer.L5_WEEKLY, week, "weekly_pnl", round(total_pnl, 2)
+                )
+
+            # Average all confidence values
+            if "avg_confidence" in daily_data:
+                conf_values = daily_data["avg_confidence"]
+                avg_conf = sum(conf_values) / len(conf_values)
+                self.store.set_context(
+                    ContextLayer.L5_WEEKLY, week, "avg_confidence", round(avg_conf, 2)
+                )
+
+    def aggregate_monthly_from_weekly(self, month: str | None = None) -> None:
+        """Aggregate L4 (monthly) context from L5 (weekly).
+
+        Args:
+            month: Month in YYYY-MM format. If None, uses current month.
+        """
+        if month is None:
+            month = datetime.now(UTC).strftime("%Y-%m")
+
+        # Get all weekly contexts for this month
+        cursor = self.conn.execute(
+            """
+            SELECT key, value FROM contexts
+            WHERE layer = ? AND timeframe LIKE ?
+            """,
+            (ContextLayer.L5_WEEKLY.value, f"{month[:4]}-W%"),
+        )
+
+        # Group by key and collect all values
+        import json
+        from collections import defaultdict
+
+        weekly_data: dict[str, list[Any]] = defaultdict(list)
+        for row in cursor.fetchall():
+            weekly_data[row[0]].append(json.loads(row[1]))
+
+        if weekly_data:
+            # Sum all weekly PnL values
+            if "weekly_pnl" in weekly_data:
+                total_pnl = sum(weekly_data["weekly_pnl"])
+                self.store.set_context(
+                    ContextLayer.L4_MONTHLY, month, "monthly_pnl", round(total_pnl, 2)
+                )
+
+    def aggregate_quarterly_from_monthly(self, quarter: str | None = None) -> None:
+        """Aggregate L3 (quarterly) context from L4 (monthly).
+
+        Args:
+            quarter: Quarter in YYYY-Qn format. If None, uses current quarter.
+        """
+        if quarter is None:
+            from datetime import datetime
+
+            now = datetime.now(UTC)
+            q = (now.month - 1) // 3 + 1
+            quarter = f"{now.year}-Q{q}"
+
+        # Get all monthly contexts for this quarter
+        # Q1: 01-03, Q2: 04-06, Q3: 07-09, Q4: 10-12
+        q_num = int(quarter.split("-Q")[1])
+        months = [f"{quarter[:4]}-{m:02d}" for m in range((q_num - 1) * 3 + 1, q_num * 3 + 1)]
+
+        total_pnl = 0.0
+        for month in months:
+            monthly_pnl = self.store.get_context(
+                ContextLayer.L4_MONTHLY, month, "monthly_pnl"
+            )
+            if monthly_pnl is not None:
+                total_pnl += monthly_pnl
+
+        self.store.set_context(
+            ContextLayer.L3_QUARTERLY, quarter, "quarterly_pnl", round(total_pnl, 2)
+        )
+
+    def aggregate_annual_from_quarterly(self, year: str | None = None) -> None:
+        """Aggregate L2 (annual) context from L3 (quarterly).
+
+        Args:
+            year: Year in YYYY format. If None, uses current year.
+        """
+        if year is None:
+            year = str(datetime.now(UTC).year)
+
+        # Get all quarterly contexts for this year
+        total_pnl = 0.0
+        for q in range(1, 5):
+            quarter = f"{year}-Q{q}"
+            quarterly_pnl = self.store.get_context(
+                ContextLayer.L3_QUARTERLY, quarter, "quarterly_pnl"
+            )
+            if quarterly_pnl is not None:
+                total_pnl += quarterly_pnl
+
+        self.store.set_context(
+            ContextLayer.L2_ANNUAL, year, "annual_pnl", round(total_pnl, 2)
+        )
+
+    def aggregate_legacy_from_annual(self) -> None:
+        """Aggregate L1 (legacy) context from all L2 (annual) data."""
+        # Get all annual PnL
+        cursor = self.conn.execute(
+            """
+            SELECT timeframe, value FROM contexts
+            WHERE layer = ? AND key = ?
+            ORDER BY timeframe
+            """,
+            (ContextLayer.L2_ANNUAL.value, "annual_pnl"),
+        )
+
+        import json
+
+        annual_data = [(row[0], json.loads(row[1])) for row in cursor.fetchall()]
+
+        if annual_data:
+            total_pnl = sum(pnl for _, pnl in annual_data)
+            years_traded = len(annual_data)
+            avg_annual_pnl = total_pnl / years_traded
+
+            # Store in L1 (single "LEGACY" timeframe)
+            self.store.set_context(
+                ContextLayer.L1_LEGACY, "LEGACY", "total_pnl", round(total_pnl, 2)
+            )
+            self.store.set_context(
+                ContextLayer.L1_LEGACY, "LEGACY", "years_traded", years_traded
+            )
+            self.store.set_context(
+                ContextLayer.L1_LEGACY,
+                "LEGACY",
+                "avg_annual_pnl",
+                round(avg_annual_pnl, 2),
+            )
+
+    def run_all_aggregations(self) -> None:
+        """Run all aggregations from L7 to L1 (bottom-up)."""
+        # L7 (trades) → L6 (daily)
+        self.aggregate_daily_from_trades()
+
+        # L6 (daily) → L5 (weekly)
+        self.aggregate_weekly_from_daily()
+
+        # L5 (weekly) → L4 (monthly)
+        self.aggregate_monthly_from_weekly()
+
+        # L4 (monthly) → L3 (quarterly)
+        self.aggregate_quarterly_from_monthly()
+
+        # L3 (quarterly) → L2 (annual)
+        self.aggregate_annual_from_quarterly()
+
+        # L2 (annual) → L1 (legacy)
+        self.aggregate_legacy_from_annual()

src/context/layer.py

@@ -0,0 +1,75 @@
+"""Context layer definitions for multi-tier memory management."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from enum import Enum
+
+
+class ContextLayer(str, Enum):
+    """7-tier context hierarchy from real-time to generational."""
+
+    L1_LEGACY = "L1_LEGACY"  # Cumulative/generational wisdom
+    L2_ANNUAL = "L2_ANNUAL"  # Yearly performance
+    L3_QUARTERLY = "L3_QUARTERLY"  # Quarterly strategy adjustments
+    L4_MONTHLY = "L4_MONTHLY"  # Monthly rebalancing
+    L5_WEEKLY = "L5_WEEKLY"  # Weekly stock selection
+    L6_DAILY = "L6_DAILY"  # Daily trade logs
+    L7_REALTIME = "L7_REALTIME"  # Real-time market data
+
+
+@dataclass(frozen=True)
+class LayerMetadata:
+    """Metadata for each context layer."""
+
+    layer: ContextLayer
+    description: str
+    retention_days: int | None  # None = keep forever
+    aggregation_source: ContextLayer | None  # Parent layer for aggregation
+
+
+# Layer configuration
+LAYER_CONFIG: dict[ContextLayer, LayerMetadata] = {
+    ContextLayer.L1_LEGACY: LayerMetadata(
+        layer=ContextLayer.L1_LEGACY,
+        description="Cumulative trading history and core lessons learned across generations",
+        retention_days=None,  # Keep forever
+        aggregation_source=ContextLayer.L2_ANNUAL,
+    ),
+    ContextLayer.L2_ANNUAL: LayerMetadata(
+        layer=ContextLayer.L2_ANNUAL,
+        description="Yearly returns, Sharpe ratio, max drawdown, win rate",
+        retention_days=365 * 10,  # 10 years
+        aggregation_source=ContextLayer.L3_QUARTERLY,
+    ),
+    ContextLayer.L3_QUARTERLY: LayerMetadata(
+        layer=ContextLayer.L3_QUARTERLY,
+        description="Quarterly strategy adjustments, market phase detection, sector rotation",
+        retention_days=365 * 3,  # 3 years
+        aggregation_source=ContextLayer.L4_MONTHLY,
+    ),
+    ContextLayer.L4_MONTHLY: LayerMetadata(
+        layer=ContextLayer.L4_MONTHLY,
+        description="Monthly portfolio rebalancing, risk exposure, drawdown recovery",
+        retention_days=365 * 2,  # 2 years
+        aggregation_source=ContextLayer.L5_WEEKLY,
+    ),
+    ContextLayer.L5_WEEKLY: LayerMetadata(
+        layer=ContextLayer.L5_WEEKLY,
+        description="Weekly stock selection, sector focus, volatility regime",
+        retention_days=365,  # 1 year
+        aggregation_source=ContextLayer.L6_DAILY,
+    ),
+    ContextLayer.L6_DAILY: LayerMetadata(
+        layer=ContextLayer.L6_DAILY,
+        description="Daily trade logs, P&L, market summaries, decision accuracy",
+        retention_days=90,  # 90 days
+        aggregation_source=ContextLayer.L7_REALTIME,
+    ),
+    ContextLayer.L7_REALTIME: LayerMetadata(
+        layer=ContextLayer.L7_REALTIME,
+        description="Real-time positions, quotes, orderbook, volatility, live P&L",
+        retention_days=7,  # 7 days (real-time data is ephemeral)
+        aggregation_source=None,  # No aggregation source (leaf layer)
+    ),
+}

src/context/store.py

@@ -0,0 +1,193 @@
+"""Context storage and retrieval for the 7-tier memory system."""
+
+from __future__ import annotations
+
+import json
+import sqlite3
+from datetime import UTC, datetime
+from typing import Any
+
+from src.context.layer import LAYER_CONFIG, ContextLayer
+
+
+class ContextStore:
+    """Manages context data across the 7-tier hierarchy."""
+
+    def __init__(self, conn: sqlite3.Connection) -> None:
+        """Initialize the context store with a database connection."""
+        self.conn = conn
+        self._init_metadata()
+
+    def _init_metadata(self) -> None:
+        """Initialize context_metadata table with layer configurations."""
+        for config in LAYER_CONFIG.values():
+            self.conn.execute(
+                """
+                INSERT OR REPLACE INTO context_metadata
+                (layer, description, retention_days, aggregation_source)
+                VALUES (?, ?, ?, ?)
+                """,
+                (
+                    config.layer.value,
+                    config.description,
+                    config.retention_days,
+                    config.aggregation_source.value if config.aggregation_source else None,
+                ),
+            )
+        self.conn.commit()
+
+    def set_context(
+        self,
+        layer: ContextLayer,
+        timeframe: str,
+        key: str,
+        value: Any,
+    ) -> None:
+        """Set a context value for a given layer and timeframe.
+
+        Args:
+            layer: The context layer (L1-L7)
+            timeframe: Time identifier (e.g., "2026", "2026-Q1", "2026-01",
+                "2026-W05", "2026-02-04")
+            key: Context key (e.g., "sharpe_ratio", "win_rate", "lesson_learned")
+            value: Context value (will be JSON-serialized)
+        """
+        now = datetime.now(UTC).isoformat()
+        value_json = json.dumps(value)
+
+        self.conn.execute(
+            """
+            INSERT INTO contexts (layer, timeframe, key, value, created_at, updated_at)
+            VALUES (?, ?, ?, ?, ?, ?)
+            ON CONFLICT(layer, timeframe, key)
+            DO UPDATE SET value = excluded.value, updated_at = excluded.updated_at
+            """,
+            (layer.value, timeframe, key, value_json, now, now),
+        )
+        self.conn.commit()
+
+    def get_context(
+        self,
+        layer: ContextLayer,
+        timeframe: str,
+        key: str,
+    ) -> Any | None:
+        """Get a context value for a given layer and timeframe.
+
+        Args:
+            layer: The context layer (L1-L7)
+            timeframe: Time identifier
+            key: Context key
+
+        Returns:
+            The context value (deserialized from JSON), or None if not found
+        """
+        cursor = self.conn.execute(
+            """
+            SELECT value FROM contexts
+            WHERE layer = ? AND timeframe = ? AND key = ?
+            """,
+            (layer.value, timeframe, key),
+        )
+        row = cursor.fetchone()
+        if row:
+            return json.loads(row[0])
+        return None
+
+    def get_all_contexts(
+        self,
+        layer: ContextLayer,
+        timeframe: str | None = None,
+    ) -> dict[str, Any]:
+        """Get all context values for a given layer and optional timeframe.
+
+        Args:
+            layer: The context layer (L1-L7)
+            timeframe: Optional time identifier filter
+
+        Returns:
+            Dictionary of key-value pairs for the specified layer/timeframe
+        """
+        if timeframe:
+            cursor = self.conn.execute(
+                """
+                SELECT key, value FROM contexts
+                WHERE layer = ? AND timeframe = ?
+                ORDER BY key
+                """,
+                (layer.value, timeframe),
+            )
+        else:
+            cursor = self.conn.execute(
+                """
+                SELECT key, value FROM contexts
+                WHERE layer = ?
+                ORDER BY timeframe DESC, key
+                """,
+                (layer.value,),
+            )
+
+        return {row[0]: json.loads(row[1]) for row in cursor.fetchall()}
+
+    def get_latest_timeframe(self, layer: ContextLayer) -> str | None:
+        """Get the most recent timeframe for a given layer.
+
+        Args:
+            layer: The context layer (L1-L7)
+
+        Returns:
+            The latest timeframe string, or None if no data exists
+        """
+        cursor = self.conn.execute(
+            """
+            SELECT timeframe FROM contexts
+            WHERE layer = ?
+            ORDER BY updated_at DESC
+            LIMIT 1
+            """,
+            (layer.value,),
+        )
+        row = cursor.fetchone()
+        return row[0] if row else None
+
+    def delete_old_contexts(self, layer: ContextLayer, cutoff_date: str) -> int:
+        """Delete contexts older than the cutoff date for a given layer.
+
+        Args:
+            layer: The context layer (L1-L7)
+            cutoff_date: ISO format date string (contexts before this will be deleted)
+
+        Returns:
+            Number of rows deleted
+        """
+        cursor = self.conn.execute(
+            """
+            DELETE FROM contexts
+            WHERE layer = ? AND updated_at < ?
+            """,
+            (layer.value, cutoff_date),
+        )
+        self.conn.commit()
+        return cursor.rowcount
+
+    def cleanup_expired_contexts(self) -> dict[ContextLayer, int]:
+        """Delete expired contexts based on retention policies.
+
+        Returns:
+            Dictionary mapping layer to number of deleted rows
+        """
+        deleted_counts: dict[ContextLayer, int] = {}
+
+        for layer, config in LAYER_CONFIG.items():
+            if config.retention_days is None:
+                # Keep forever (e.g., L1_LEGACY)
+                deleted_counts[layer] = 0
+                continue
+
+            # Calculate cutoff date
+            from datetime import timedelta
+
+            cutoff = datetime.now(UTC) - timedelta(days=config.retention_days)
+            deleted_counts[layer] = self.delete_old_contexts(layer, cutoff.isoformat())
+
+        return deleted_counts

src/context/summarizer.py

@@ -0,0 +1,328 @@
+"""Context summarization for efficient historical data representation.
+
+This module summarizes old context data instead of including raw details:
+- Key metrics only (averages, trends, not details)
+- Rolling window (keep last N days detailed, summarize older)
+- Aggregate historical data efficiently
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from datetime import UTC, datetime, timedelta
+from typing import Any
+
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+
+
+@dataclass(frozen=True)
+class SummaryStats:
+    """Statistical summary of historical data."""
+
+    count: int
+    mean: float | None = None
+    min: float | None = None
+    max: float | None = None
+    std: float | None = None
+    trend: str | None = None  # "up", "down", "flat"
+
+
+class ContextSummarizer:
+    """Summarizes historical context data to reduce token usage."""
+
+    def __init__(self, store: ContextStore) -> None:
+        """Initialize the context summarizer.
+
+        Args:
+            store: ContextStore instance for retrieving context data
+        """
+        self.store = store
+
+    def summarize_numeric_values(self, values: list[float]) -> SummaryStats:
+        """Summarize a list of numeric values.
+
+        Args:
+            values: List of numeric values to summarize
+
+        Returns:
+            SummaryStats with mean, min, max, std, and trend
+        """
+        if not values:
+            return SummaryStats(count=0)
+
+        count = len(values)
+        mean = sum(values) / count
+        min_val = min(values)
+        max_val = max(values)
+
+        # Calculate standard deviation
+        if count > 1:
+            variance = sum((x - mean) ** 2 for x in values) / (count - 1)
+            std = variance**0.5
+        else:
+            std = 0.0
+
+        # Determine trend
+        trend = "flat"
+        if count >= 3:
+            # Simple trend: compare first third vs last third
+            first_third = values[: count // 3]
+            last_third = values[-(count // 3) :]
+            first_avg = sum(first_third) / len(first_third)
+            last_avg = sum(last_third) / len(last_third)
+
+            # Trend threshold: 5% change
+            threshold = 0.05 * abs(first_avg) if first_avg != 0 else 0.01
+
+            if last_avg > first_avg + threshold:
+                trend = "up"
+            elif last_avg < first_avg - threshold:
+                trend = "down"
+
+        return SummaryStats(
+            count=count,
+            mean=round(mean, 4),
+            min=round(min_val, 4),
+            max=round(max_val, 4),
+            std=round(std, 4),
+            trend=trend,
+        )
+
+    def summarize_layer(
+        self,
+        layer: ContextLayer,
+        start_date: datetime | None = None,
+        end_date: datetime | None = None,
+    ) -> dict[str, Any]:
+        """Summarize all context data for a layer within a date range.
+
+        Args:
+            layer: Context layer to summarize
+            start_date: Start date (inclusive), None for all
+            end_date: End date (inclusive), None for now
+
+        Returns:
+            Dictionary with summarized metrics
+        """
+        if end_date is None:
+            end_date = datetime.now(UTC)
+
+        # Get all contexts for this layer
+        all_contexts = self.store.get_all_contexts(layer)
+
+        if not all_contexts:
+            return {"summary": "No data available", "count": 0}
+
+        # Group numeric values by key
+        numeric_data: dict[str, list[float]] = {}
+        text_data: dict[str, list[str]] = {}
+
+        for key, value in all_contexts.items():
+            # Try to extract numeric values
+            if isinstance(value, (int, float)):
+                if key not in numeric_data:
+                    numeric_data[key] = []
+                numeric_data[key].append(float(value))
+            elif isinstance(value, dict):
+                # Extract numeric fields from dict
+                for subkey, subvalue in value.items():
+                    if isinstance(subvalue, (int, float)):
+                        full_key = f"{key}.{subkey}"
+                        if full_key not in numeric_data:
+                            numeric_data[full_key] = []
+                        numeric_data[full_key].append(float(subvalue))
+            elif isinstance(value, str):
+                if key not in text_data:
+                    text_data[key] = []
+                text_data[key].append(value)
+
+        # Summarize numeric data
+        summary: dict[str, Any] = {}
+
+        for key, values in numeric_data.items():
+            stats = self.summarize_numeric_values(values)
+            summary[key] = {
+                "count": stats.count,
+                "avg": stats.mean,
+                "range": [stats.min, stats.max],
+                "trend": stats.trend,
+            }
+
+        # Summarize text data (just counts)
+        for key, values in text_data.items():
+            summary[f"{key}_count"] = len(values)
+
+        summary["total_entries"] = len(all_contexts)
+
+        return summary
+
+    def rolling_window_summary(
+        self,
+        layer: ContextLayer,
+        window_days: int = 30,
+        summarize_older: bool = True,
+    ) -> dict[str, Any]:
+        """Create a rolling window summary.
+
+        Recent data (within window) is kept detailed.
+        Older data is summarized to key metrics.
+
+        Args:
+            layer: Context layer to summarize
+            window_days: Number of days to keep detailed
+            summarize_older: Whether to summarize data older than window
+
+        Returns:
+            Dictionary with recent (detailed) and historical (summary) data
+        """
+        result: dict[str, Any] = {
+            "window_days": window_days,
+            "recent_data": {},
+            "historical_summary": {},
+        }
+
+        # Get all contexts
+        all_contexts = self.store.get_all_contexts(layer)
+
+        recent_values: dict[str, list[float]] = {}
+        historical_values: dict[str, list[float]] = {}
+
+        for key, value in all_contexts.items():
+            # For simplicity, treat all numeric values
+            if isinstance(value, (int, float)):
+                # Note: We don't have timestamps in context keys
+                # This is a simplified implementation
+                # In practice, would need to check timeframe field
+
+                # For now, put recent data in window
+                if key not in recent_values:
+                    recent_values[key] = []
+                recent_values[key].append(float(value))
+
+        # Detailed recent data
+        result["recent_data"] = {key: values[-10:] for key, values in recent_values.items()}
+
+        # Summarized historical data
+        if summarize_older:
+            for key, values in historical_values.items():
+                stats = self.summarize_numeric_values(values)
+                result["historical_summary"][key] = {
+                    "count": stats.count,
+                    "avg": stats.mean,
+                    "trend": stats.trend,
+                }
+
+        return result
+
+    def aggregate_to_higher_layer(
+        self,
+        source_layer: ContextLayer,
+        target_layer: ContextLayer,
+        metric_key: str,
+        aggregation_func: str = "mean",
+    ) -> float | None:
+        """Aggregate data from source layer to target layer.
+
+        Args:
+            source_layer: Source context layer (more granular)
+            target_layer: Target context layer (less granular)
+            metric_key: Key of metric to aggregate
+            aggregation_func: Aggregation function ("mean", "sum", "max", "min")
+
+        Returns:
+            Aggregated value, or None if no data available
+        """
+        # Get all contexts from source layer
+        source_contexts = self.store.get_all_contexts(source_layer)
+
+        # Extract values for metric_key
+        values = []
+        for key, value in source_contexts.items():
+            if key == metric_key and isinstance(value, (int, float)):
+                values.append(float(value))
+            elif isinstance(value, dict) and metric_key in value:
+                subvalue = value[metric_key]
+                if isinstance(subvalue, (int, float)):
+                    values.append(float(subvalue))
+
+        if not values:
+            return None
+
+        # Apply aggregation function
+        if aggregation_func == "mean":
+            return sum(values) / len(values)
+        elif aggregation_func == "sum":
+            return sum(values)
+        elif aggregation_func == "max":
+            return max(values)
+        elif aggregation_func == "min":
+            return min(values)
+        else:
+            return sum(values) / len(values)  # Default to mean
+
+    def create_compact_summary(
+        self,
+        layers: list[ContextLayer],
+        top_n_metrics: int = 5,
+    ) -> dict[str, Any]:
+        """Create a compact summary across multiple layers.
+
+        Args:
+            layers: List of context layers to summarize
+            top_n_metrics: Number of top metrics to include per layer
+
+        Returns:
+            Compact summary dictionary
+        """
+        summary: dict[str, Any] = {}
+
+        for layer in layers:
+            layer_summary = self.summarize_layer(layer)
+
+            # Keep only top N metrics (by count/relevance)
+            metrics = []
+            for key, value in layer_summary.items():
+                if isinstance(value, dict) and "count" in value:
+                    metrics.append((key, value, value["count"]))
+
+            # Sort by count (descending)
+            metrics.sort(key=lambda x: x[2], reverse=True)
+
+            # Keep top N
+            top_metrics = {m[0]: m[1] for m in metrics[:top_n_metrics]}
+
+            summary[layer.value] = top_metrics
+
+        return summary
+
+    def format_summary_for_prompt(self, summary: dict[str, Any]) -> str:
+        """Format summary for inclusion in a prompt.
+
+        Args:
+            summary: Summary dictionary
+
+        Returns:
+            Formatted string for prompt
+        """
+        lines = []
+
+        for layer, metrics in summary.items():
+            if not metrics:
+                continue
+
+            lines.append(f"{layer}:")
+            for key, value in metrics.items():
+                if isinstance(value, dict):
+                    # Format as: key: avg=X, trend=Y
+                    parts = []
+                    if "avg" in value and value["avg"] is not None:
+                        parts.append(f"avg={value['avg']:.2f}")
+                    if "trend" in value and value["trend"]:
+                        parts.append(f"trend={value['trend']}")
+                    if parts:
+                        lines.append(f"  {key}: {', '.join(parts)}")
+                else:
+                    lines.append(f"  {key}: {value}")
+
+        return "\n".join(lines)

src/core/criticality.py

@@ -0,0 +1,110 @@
+"""Criticality assessment for urgency-based response system.
+
+Evaluates market conditions to determine response urgency and enable
+faster reactions in critical situations.
+"""
+
+from __future__ import annotations
+
+from enum import StrEnum
+
+
+class CriticalityLevel(StrEnum):
+    """Urgency levels for market conditions and trading decisions."""
+
+    CRITICAL = "CRITICAL"  # <5s timeout - Emergency response required
+    HIGH = "HIGH"  # <30s timeout - Elevated priority
+    NORMAL = "NORMAL"  # <60s timeout - Standard processing
+    LOW = "LOW"  # No timeout - Batch processing
+
+
+class CriticalityAssessor:
+    """Assesses market conditions to determine response criticality level."""
+
+    def __init__(
+        self,
+        critical_pnl_threshold: float = -2.5,
+        critical_price_change_threshold: float = 5.0,
+        critical_volume_surge_threshold: float = 10.0,
+        high_volatility_threshold: float = 70.0,
+        low_volatility_threshold: float = 30.0,
+    ) -> None:
+        """Initialize the criticality assessor.
+
+        Args:
+            critical_pnl_threshold: P&L % that triggers CRITICAL (default -2.5%)
+            critical_price_change_threshold: Price change % that triggers CRITICAL
+                (default 5.0% in 1 minute)
+            critical_volume_surge_threshold: Volume surge ratio that triggers CRITICAL
+                (default 10x average)
+            high_volatility_threshold: Volatility score that triggers HIGH
+                (default 70.0)
+            low_volatility_threshold: Volatility score below which is LOW
+                (default 30.0)
+        """
+        self.critical_pnl_threshold = critical_pnl_threshold
+        self.critical_price_change_threshold = critical_price_change_threshold
+        self.critical_volume_surge_threshold = critical_volume_surge_threshold
+        self.high_volatility_threshold = high_volatility_threshold
+        self.low_volatility_threshold = low_volatility_threshold
+
+    def assess_market_conditions(
+        self,
+        pnl_pct: float,
+        volatility_score: float,
+        volume_surge: float,
+        price_change_1m: float = 0.0,
+        is_market_open: bool = True,
+    ) -> CriticalityLevel:
+        """Assess criticality level based on market conditions.
+
+        Args:
+            pnl_pct: Current P&L percentage
+            volatility_score: Momentum score from VolatilityAnalyzer (0-100)
+            volume_surge: Volume surge ratio (current / average)
+            price_change_1m: 1-minute price change percentage
+            is_market_open: Whether the market is currently open
+
+        Returns:
+            CriticalityLevel indicating required response urgency
+        """
+        # Market closed or very quiet → LOW priority (batch processing)
+        if not is_market_open or volatility_score < self.low_volatility_threshold:
+            return CriticalityLevel.LOW
+
+        # CRITICAL conditions: immediate action required
+        # 1. P&L near circuit breaker (-2.5% is close to -3.0% breaker)
+        if pnl_pct <= self.critical_pnl_threshold:
+            return CriticalityLevel.CRITICAL
+
+        # 2. Large sudden price movement (>5% in 1 minute)
+        if abs(price_change_1m) >= self.critical_price_change_threshold:
+            return CriticalityLevel.CRITICAL
+
+        # 3. Extreme volume surge (>10x average) indicates major event
+        if volume_surge >= self.critical_volume_surge_threshold:
+            return CriticalityLevel.CRITICAL
+
+        # HIGH priority: elevated volatility requires faster response
+        if volatility_score >= self.high_volatility_threshold:
+            return CriticalityLevel.HIGH
+
+        # NORMAL: standard trading conditions
+        return CriticalityLevel.NORMAL
+
+    def get_timeout(self, level: CriticalityLevel) -> float | None:
+        """Get timeout in seconds for a given criticality level.
+
+        Args:
+            level: Criticality level
+
+        Returns:
+            Timeout in seconds, or None for no timeout (LOW priority)
+        """
+        timeout_map = {
+            CriticalityLevel.CRITICAL: 5.0,
+            CriticalityLevel.HIGH: 30.0,
+            CriticalityLevel.NORMAL: 60.0,
+            CriticalityLevel.LOW: None,
+        }
+        return timeout_map[level]

src/core/priority_queue.py

@@ -0,0 +1,291 @@
+"""Priority-based task queue for latency control.
+
+Implements a thread-safe priority queue with timeout enforcement and metrics tracking.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import heapq
+import logging
+import time
+from collections.abc import Callable, Coroutine
+from dataclasses import dataclass, field
+from typing import Any
+
+from src.core.criticality import CriticalityLevel
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass(order=True)
+class PriorityTask:
+    """Task with priority and timestamp for queue ordering."""
+
+    # Lower priority value = higher urgency (CRITICAL=0, HIGH=1, NORMAL=2, LOW=3)
+    priority: int
+    timestamp: float
+    # Task data not used in comparison
+    task_id: str = field(compare=False)
+    task_data: dict[str, Any] = field(compare=False, default_factory=dict)
+    callback: Callable[[], Coroutine[Any, Any, Any]] | None = field(
+        compare=False, default=None
+    )
+
+
+@dataclass
+class QueueMetrics:
+    """Metrics for priority queue performance monitoring."""
+
+    total_enqueued: int = 0
+    total_dequeued: int = 0
+    total_timeouts: int = 0
+    total_errors: int = 0
+    current_size: int = 0
+    # Average wait time per criticality level (in seconds)
+    avg_wait_time: dict[CriticalityLevel, float] = field(default_factory=dict)
+    # P95 wait time per criticality level
+    p95_wait_time: dict[CriticalityLevel, float] = field(default_factory=dict)
+
+
+class PriorityTaskQueue:
+    """Thread-safe priority queue with timeout enforcement."""
+
+    # Priority mapping for criticality levels
+    PRIORITY_MAP = {
+        CriticalityLevel.CRITICAL: 0,
+        CriticalityLevel.HIGH: 1,
+        CriticalityLevel.NORMAL: 2,
+        CriticalityLevel.LOW: 3,
+    }
+
+    def __init__(self, max_size: int = 1000) -> None:
+        """Initialize the priority task queue.
+
+        Args:
+            max_size: Maximum queue size (default 1000)
+        """
+        self._queue: list[PriorityTask] = []
+        self._lock = asyncio.Lock()
+        self._max_size = max_size
+        self._metrics = QueueMetrics()
+        # Track wait times for metrics
+        self._wait_times: dict[CriticalityLevel, list[float]] = {
+            level: [] for level in CriticalityLevel
+        }
+
+    async def enqueue(
+        self,
+        task_id: str,
+        criticality: CriticalityLevel,
+        task_data: dict[str, Any],
+        callback: Callable[[], Coroutine[Any, Any, Any]] | None = None,
+    ) -> bool:
+        """Add a task to the priority queue.
+
+        Args:
+            task_id: Unique identifier for the task
+            criticality: Criticality level determining priority
+            task_data: Data associated with the task
+            callback: Optional async callback to execute
+
+        Returns:
+            True if enqueued successfully, False if queue is full
+        """
+        async with self._lock:
+            if len(self._queue) >= self._max_size:
+                logger.warning(
+                    "Priority queue full (size=%d), rejecting task %s",
+                    len(self._queue),
+                    task_id,
+                )
+                return False
+
+            priority = self.PRIORITY_MAP[criticality]
+            timestamp = time.time()
+
+            task = PriorityTask(
+                priority=priority,
+                timestamp=timestamp,
+                task_id=task_id,
+                task_data=task_data,
+                callback=callback,
+            )
+
+            heapq.heappush(self._queue, task)
+            self._metrics.total_enqueued += 1
+            self._metrics.current_size = len(self._queue)
+
+            logger.debug(
+                "Enqueued task %s with criticality %s (priority=%d, queue_size=%d)",
+                task_id,
+                criticality.value,
+                priority,
+                len(self._queue),
+            )
+
+            return True
+
+    async def dequeue(self, timeout: float | None = None) -> PriorityTask | None:
+        """Remove and return the highest priority task from the queue.
+
+        Args:
+            timeout: Maximum time to wait for a task (seconds)
+
+        Returns:
+            PriorityTask if available, None if queue is empty or timeout
+        """
+        start_time = time.time()
+        deadline = start_time + timeout if timeout else None
+
+        while True:
+            async with self._lock:
+                if self._queue:
+                    task = heapq.heappop(self._queue)
+                    self._metrics.total_dequeued += 1
+                    self._metrics.current_size = len(self._queue)
+
+                    # Calculate wait time
+                    wait_time = time.time() - task.timestamp
+                    criticality = self._get_criticality_from_priority(task.priority)
+                    self._wait_times[criticality].append(wait_time)
+                    self._update_wait_time_metrics()
+
+                    logger.debug(
+                        "Dequeued task %s (priority=%d, wait_time=%.2fs, queue_size=%d)",
+                        task.task_id,
+                        task.priority,
+                        wait_time,
+                        len(self._queue),
+                    )
+
+                    return task
+
+            # Queue is empty
+            if deadline and time.time() >= deadline:
+                return None
+
+            # Wait a bit before checking again
+            await asyncio.sleep(0.1)
+
+    async def execute_with_timeout(
+        self,
+        task: PriorityTask,
+        timeout: float | None,
+    ) -> Any:
+        """Execute a task with timeout enforcement.
+
+        Args:
+            task: Task to execute
+            timeout: Timeout in seconds (None = no timeout)
+
+        Returns:
+            Result from task callback
+
+        Raises:
+            asyncio.TimeoutError: If task exceeds timeout
+            Exception: Any exception raised by the task callback
+        """
+        if not task.callback:
+            logger.warning("Task %s has no callback, skipping execution", task.task_id)
+            return None
+
+        criticality = self._get_criticality_from_priority(task.priority)
+
+        try:
+            if timeout:
+                result = await asyncio.wait_for(task.callback(), timeout=timeout)
+            else:
+                result = await task.callback()
+
+            logger.debug(
+                "Task %s completed successfully (criticality=%s)",
+                task.task_id,
+                criticality.value,
+            )
+            return result
+
+        except TimeoutError:
+            self._metrics.total_timeouts += 1
+            logger.error(
+                "Task %s timed out after %.2fs (criticality=%s)",
+                task.task_id,
+                timeout or 0.0,
+                criticality.value,
+            )
+            raise
+
+        except Exception as exc:
+            self._metrics.total_errors += 1
+            logger.exception(
+                "Task %s failed with error (criticality=%s): %s",
+                task.task_id,
+                criticality.value,
+                exc,
+            )
+            raise
+
+    def _get_criticality_from_priority(self, priority: int) -> CriticalityLevel:
+        """Convert priority back to criticality level."""
+        for level, prio in self.PRIORITY_MAP.items():
+            if prio == priority:
+                return level
+        return CriticalityLevel.NORMAL
+
+    def _update_wait_time_metrics(self) -> None:
+        """Update average and p95 wait time metrics."""
+        for level, times in self._wait_times.items():
+            if not times:
+                continue
+
+            # Keep only last 1000 measurements to avoid memory bloat
+            if len(times) > 1000:
+                self._wait_times[level] = times[-1000:]
+                times = self._wait_times[level]
+
+            # Calculate average
+            self._metrics.avg_wait_time[level] = sum(times) / len(times)
+
+            # Calculate P95
+            sorted_times = sorted(times)
+            p95_idx = int(len(sorted_times) * 0.95)
+            self._metrics.p95_wait_time[level] = sorted_times[p95_idx]
+
+    async def get_metrics(self) -> QueueMetrics:
+        """Get current queue metrics.
+
+        Returns:
+            QueueMetrics with current statistics
+        """
+        async with self._lock:
+            return QueueMetrics(
+                total_enqueued=self._metrics.total_enqueued,
+                total_dequeued=self._metrics.total_dequeued,
+                total_timeouts=self._metrics.total_timeouts,
+                total_errors=self._metrics.total_errors,
+                current_size=self._metrics.current_size,
+                avg_wait_time=dict(self._metrics.avg_wait_time),
+                p95_wait_time=dict(self._metrics.p95_wait_time),
+            )
+
+    async def size(self) -> int:
+        """Get current queue size.
+
+        Returns:
+            Number of tasks in queue
+        """
+        async with self._lock:
+            return len(self._queue)
+
+    async def clear(self) -> int:
+        """Clear all tasks from the queue.
+
+        Returns:
+            Number of tasks cleared
+        """
+        async with self._lock:
+            count = len(self._queue)
+            self._queue.clear()
+            self._metrics.current_size = 0
+            logger.info("Cleared %d tasks from priority queue", count)
+            return count

src/db.py

@@ -39,6 +39,70 @@ def init_db(db_path: str) -> sqlite3.Connection:
     if "exchange_code" not in columns:
         conn.execute("ALTER TABLE trades ADD COLUMN exchange_code TEXT DEFAULT 'KRX'")
 
+    # Context tree tables for multi-layered memory management
+    conn.execute(
+        """
+        CREATE TABLE IF NOT EXISTS contexts (
+            id INTEGER PRIMARY KEY AUTOINCREMENT,
+            layer TEXT NOT NULL,
+            timeframe TEXT NOT NULL,
+            key TEXT NOT NULL,
+            value TEXT NOT NULL,
+            created_at TEXT NOT NULL,
+            updated_at TEXT NOT NULL,
+            UNIQUE(layer, timeframe, key)
+        )
+        """
+    )
+
+    # Decision logging table for comprehensive audit trail
+    conn.execute(
+        """
+        CREATE TABLE IF NOT EXISTS decision_logs (
+            decision_id TEXT PRIMARY KEY,
+            timestamp TEXT NOT NULL,
+            stock_code TEXT NOT NULL,
+            market TEXT NOT NULL,
+            exchange_code TEXT NOT NULL,
+            action TEXT NOT NULL,
+            confidence INTEGER NOT NULL,
+            rationale TEXT NOT NULL,
+            context_snapshot TEXT NOT NULL,
+            input_data TEXT NOT NULL,
+            outcome_pnl REAL,
+            outcome_accuracy INTEGER,
+            reviewed INTEGER DEFAULT 0,
+            review_notes TEXT
+        )
+        """
+    )
+
+    conn.execute(
+        """
+        CREATE TABLE IF NOT EXISTS context_metadata (
+            layer TEXT PRIMARY KEY,
+            description TEXT NOT NULL,
+            retention_days INTEGER,
+            aggregation_source TEXT
+        )
+        """
+    )
+
+    # Create indices for efficient context queries
+    conn.execute("CREATE INDEX IF NOT EXISTS idx_contexts_layer ON contexts(layer)")
+    conn.execute("CREATE INDEX IF NOT EXISTS idx_contexts_timeframe ON contexts(timeframe)")
+    conn.execute("CREATE INDEX IF NOT EXISTS idx_contexts_updated ON contexts(updated_at)")
+
+    # Create indices for efficient decision log queries
+    conn.execute(
+        "CREATE INDEX IF NOT EXISTS idx_decision_logs_timestamp ON decision_logs(timestamp)"
+    )
+    conn.execute(
+        "CREATE INDEX IF NOT EXISTS idx_decision_logs_reviewed ON decision_logs(reviewed)"
+    )
+    conn.execute(
+        "CREATE INDEX IF NOT EXISTS idx_decision_logs_confidence ON decision_logs(confidence)"
+    )
     conn.commit()
     return conn
 

src/evolution/__init__.py

@@ -0,0 +1,19 @@
+"""Evolution engine for self-improving trading strategies."""
+
+from src.evolution.ab_test import ABTester, ABTestResult, StrategyPerformance
+from src.evolution.optimizer import EvolutionOptimizer
+from src.evolution.performance_tracker import (
+    PerformanceDashboard,
+    PerformanceTracker,
+    StrategyMetrics,
+)
+
+__all__ = [
+    "EvolutionOptimizer",
+    "ABTester",
+    "ABTestResult",
+    "StrategyPerformance",
+    "PerformanceTracker",
+    "PerformanceDashboard",
+    "StrategyMetrics",
+]

src/evolution/ab_test.py

@@ -0,0 +1,220 @@
+"""A/B Testing framework for strategy comparison.
+
+Runs multiple strategies in parallel, tracks their performance,
+and uses statistical significance testing to determine winners.
+"""
+
+from __future__ import annotations
+
+import logging
+from dataclasses import dataclass
+from typing import Any
+
+import scipy.stats as stats
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class StrategyPerformance:
+    """Performance metrics for a single strategy."""
+
+    strategy_name: str
+    total_trades: int
+    wins: int
+    losses: int
+    total_pnl: float
+    avg_pnl: float
+    win_rate: float
+    sharpe_ratio: float | None = None
+
+
+@dataclass
+class ABTestResult:
+    """Result of an A/B test between two strategies."""
+
+    strategy_a: str
+    strategy_b: str
+    winner: str | None
+    p_value: float
+    confidence_level: float
+    is_significant: bool
+    performance_a: StrategyPerformance
+    performance_b: StrategyPerformance
+
+
+class ABTester:
+    """A/B testing framework for comparing trading strategies."""
+
+    def __init__(self, significance_level: float = 0.05) -> None:
+        """Initialize A/B tester.
+
+        Args:
+            significance_level: P-value threshold for statistical significance (default 0.05)
+        """
+        self._significance_level = significance_level
+
+    def calculate_performance(
+        self, trades: list[dict[str, Any]], strategy_name: str
+    ) -> StrategyPerformance:
+        """Calculate performance metrics for a strategy.
+
+        Args:
+            trades: List of trade records with pnl values
+            strategy_name: Name of the strategy
+
+        Returns:
+            StrategyPerformance object with calculated metrics
+        """
+        if not trades:
+            return StrategyPerformance(
+                strategy_name=strategy_name,
+                total_trades=0,
+                wins=0,
+                losses=0,
+                total_pnl=0.0,
+                avg_pnl=0.0,
+                win_rate=0.0,
+                sharpe_ratio=None,
+            )
+
+        total_trades = len(trades)
+        wins = sum(1 for t in trades if t.get("pnl", 0) > 0)
+        losses = sum(1 for t in trades if t.get("pnl", 0) < 0)
+        pnls = [t.get("pnl", 0.0) for t in trades]
+        total_pnl = sum(pnls)
+        avg_pnl = total_pnl / total_trades if total_trades > 0 else 0.0
+        win_rate = (wins / total_trades * 100) if total_trades > 0 else 0.0
+
+        # Calculate Sharpe ratio (risk-adjusted return)
+        sharpe_ratio = None
+        if len(pnls) > 1:
+            mean_return = avg_pnl
+            std_return = (
+                sum((p - mean_return) ** 2 for p in pnls) / (len(pnls) - 1)
+            ) ** 0.5
+            if std_return > 0:
+                sharpe_ratio = mean_return / std_return
+
+        return StrategyPerformance(
+            strategy_name=strategy_name,
+            total_trades=total_trades,
+            wins=wins,
+            losses=losses,
+            total_pnl=round(total_pnl, 2),
+            avg_pnl=round(avg_pnl, 2),
+            win_rate=round(win_rate, 2),
+            sharpe_ratio=round(sharpe_ratio, 4) if sharpe_ratio else None,
+        )
+
+    def compare_strategies(
+        self,
+        trades_a: list[dict[str, Any]],
+        trades_b: list[dict[str, Any]],
+        strategy_a_name: str = "Strategy A",
+        strategy_b_name: str = "Strategy B",
+    ) -> ABTestResult:
+        """Compare two strategies using statistical testing.
+
+        Uses a two-sample t-test to determine if performance difference is significant.
+
+        Args:
+            trades_a: List of trades from strategy A
+            trades_b: List of trades from strategy B
+            strategy_a_name: Name of strategy A
+            strategy_b_name: Name of strategy B
+
+        Returns:
+            ABTestResult with comparison details
+        """
+        perf_a = self.calculate_performance(trades_a, strategy_a_name)
+        perf_b = self.calculate_performance(trades_b, strategy_b_name)
+
+        # Extract PnL arrays for statistical testing
+        pnls_a = [t.get("pnl", 0.0) for t in trades_a]
+        pnls_b = [t.get("pnl", 0.0) for t in trades_b]
+
+        # Perform two-sample t-test
+        if len(pnls_a) > 1 and len(pnls_b) > 1:
+            t_stat, p_value = stats.ttest_ind(pnls_a, pnls_b, equal_var=False)
+            is_significant = p_value < self._significance_level
+            confidence_level = (1 - p_value) * 100
+        else:
+            # Not enough data for statistical test
+            p_value = 1.0
+            is_significant = False
+            confidence_level = 0.0
+
+        # Determine winner based on average PnL
+        winner = None
+        if is_significant:
+            if perf_a.avg_pnl > perf_b.avg_pnl:
+                winner = strategy_a_name
+            elif perf_b.avg_pnl > perf_a.avg_pnl:
+                winner = strategy_b_name
+
+        return ABTestResult(
+            strategy_a=strategy_a_name,
+            strategy_b=strategy_b_name,
+            winner=winner,
+            p_value=round(p_value, 4),
+            confidence_level=round(confidence_level, 2),
+            is_significant=is_significant,
+            performance_a=perf_a,
+            performance_b=perf_b,
+        )
+
+    def should_deploy(
+        self,
+        result: ABTestResult,
+        min_win_rate: float = 60.0,
+        min_trades: int = 20,
+    ) -> bool:
+        """Determine if a winning strategy should be deployed.
+
+        Args:
+            result: A/B test result
+            min_win_rate: Minimum win rate percentage for deployment (default 60%)
+            min_trades: Minimum number of trades required (default 20)
+
+        Returns:
+            True if the winning strategy meets deployment criteria
+        """
+        if not result.is_significant or result.winner is None:
+            return False
+
+        # Get performance of winning strategy
+        if result.winner == result.strategy_a:
+            winning_perf = result.performance_a
+        else:
+            winning_perf = result.performance_b
+
+        # Check deployment criteria
+        has_enough_trades = winning_perf.total_trades >= min_trades
+        has_good_win_rate = winning_perf.win_rate >= min_win_rate
+        is_profitable = winning_perf.avg_pnl > 0
+
+        meets_criteria = has_enough_trades and has_good_win_rate and is_profitable
+
+        if meets_criteria:
+            logger.info(
+                "Strategy '%s' meets deployment criteria: "
+                "win_rate=%.2f%%, trades=%d, avg_pnl=%.2f",
+                result.winner,
+                winning_perf.win_rate,
+                winning_perf.total_trades,
+                winning_perf.avg_pnl,
+            )
+        else:
+            logger.info(
+                "Strategy '%s' does NOT meet deployment criteria: "
+                "win_rate=%.2f%% (min %.2f%%), trades=%d (min %d), avg_pnl=%.2f",
+                result.winner if result.winner else "unknown",
+                winning_perf.win_rate if result.winner else 0.0,
+                min_win_rate,
+                winning_perf.total_trades if result.winner else 0,
+                min_trades,
+                winning_perf.avg_pnl if result.winner else 0.0,
+            )
+
+        return meets_criteria

src/evolution/optimizer.py

@@ -1,10 +1,10 @@
 """Evolution Engine — analyzes trade logs and generates new strategies.
 
 This module:
-1. Reads trade_logs.db to identify failing patterns
-2. Asks Gemini to generate a new strategy class
-3. Runs pytest on the generated file
-4. Creates a simulated PR if tests pass
+1. Uses DecisionLogger.get_losing_decisions() to identify failing patterns
+2. Analyzes failure patterns by time, market conditions, stock characteristics
+3. Asks Gemini to generate improved strategy recommendations
+4. Generates new strategy classes with enhanced decision-making logic
 """
 
 from __future__ import annotations
@@ -14,6 +14,7 @@ import logging
 import sqlite3
 import subprocess
 import textwrap
+from collections import Counter
 from datetime import UTC, datetime
 from pathlib import Path
 from typing import Any
@@ -21,6 +22,8 @@ from typing import Any
 from google import genai
 
 from src.config import Settings
+from src.db import init_db
+from src.logging.decision_logger import DecisionLogger
 
 logger = logging.getLogger(__name__)
 
@@ -53,29 +56,105 @@ class EvolutionOptimizer:
         self._db_path = settings.DB_PATH
         self._client = genai.Client(api_key=settings.GEMINI_API_KEY)
         self._model_name = settings.GEMINI_MODEL
+        self._conn = init_db(self._db_path)
+        self._decision_logger = DecisionLogger(self._conn)
 
     # ------------------------------------------------------------------
     # Analysis
     # ------------------------------------------------------------------
 
     def analyze_failures(self, limit: int = 50) -> list[dict[str, Any]]:
-        """Find trades where high confidence led to losses."""
-        conn = sqlite3.connect(self._db_path)
-        conn.row_factory = sqlite3.Row
-        try:
-            rows = conn.execute(
-                """
-                SELECT stock_code, action, confidence, pnl, rationale, timestamp
-                FROM trades
-                WHERE confidence >= 80 AND pnl < 0
-                ORDER BY pnl ASC
-                LIMIT ?
-                """,
-                (limit,),
-            ).fetchall()
-            return [dict(r) for r in rows]
-        finally:
-            conn.close()
+        """Find high-confidence decisions that resulted in losses.
+
+        Uses DecisionLogger.get_losing_decisions() to retrieve failures.
+        """
+        losing_decisions = self._decision_logger.get_losing_decisions(
+            min_confidence=80, min_loss=-100.0
+        )
+
+        # Limit results
+        if len(losing_decisions) > limit:
+            losing_decisions = losing_decisions[:limit]
+
+        # Convert to dict format for analysis
+        failures = []
+        for decision in losing_decisions:
+            failures.append({
+                "decision_id": decision.decision_id,
+                "timestamp": decision.timestamp,
+                "stock_code": decision.stock_code,
+                "market": decision.market,
+                "exchange_code": decision.exchange_code,
+                "action": decision.action,
+                "confidence": decision.confidence,
+                "rationale": decision.rationale,
+                "outcome_pnl": decision.outcome_pnl,
+                "outcome_accuracy": decision.outcome_accuracy,
+                "context_snapshot": decision.context_snapshot,
+                "input_data": decision.input_data,
+            })
+
+        return failures
+
+    def identify_failure_patterns(
+        self, failures: list[dict[str, Any]]
+    ) -> dict[str, Any]:
+        """Identify patterns in losing decisions.
+
+        Analyzes:
+        - Time patterns (hour of day, day of week)
+        - Market conditions (volatility, volume)
+        - Stock characteristics (price range, market)
+        - Common failure modes in rationale
+        """
+        if not failures:
+            return {"pattern_count": 0, "patterns": {}}
+
+        patterns = {
+            "markets": Counter(),
+            "actions": Counter(),
+            "hours": Counter(),
+            "avg_confidence": 0.0,
+            "avg_loss": 0.0,
+            "total_failures": len(failures),
+        }
+
+        total_confidence = 0
+        total_loss = 0.0
+
+        for failure in failures:
+            # Market distribution
+            patterns["markets"][failure.get("market", "UNKNOWN")] += 1
+
+            # Action distribution
+            patterns["actions"][failure.get("action", "UNKNOWN")] += 1
+
+            # Time pattern (extract hour from ISO timestamp)
+            timestamp = failure.get("timestamp", "")
+            if timestamp:
+                try:
+                    dt = datetime.fromisoformat(timestamp)
+                    patterns["hours"][dt.hour] += 1
+                except (ValueError, AttributeError):
+                    pass
+
+            # Aggregate metrics
+            total_confidence += failure.get("confidence", 0)
+            total_loss += failure.get("outcome_pnl", 0.0)
+
+        patterns["avg_confidence"] = (
+            round(total_confidence / len(failures), 2) if failures else 0.0
+        )
+        patterns["avg_loss"] = (
+            round(total_loss / len(failures), 2) if failures else 0.0
+        )
+
+        # Convert Counters to regular dicts for JSON serialization
+        patterns["markets"] = dict(patterns["markets"])
+        patterns["actions"] = dict(patterns["actions"])
+        patterns["hours"] = dict(patterns["hours"])
+
+        return patterns
 
     def get_performance_summary(self) -> dict[str, Any]:
         """Return aggregate performance metrics from trade logs."""
@@ -109,14 +188,25 @@ class EvolutionOptimizer:
     async def generate_strategy(self, failures: list[dict[str, Any]]) -> Path | None:
         """Ask Gemini to generate a new strategy based on failure analysis.
 
+        Integrates failure patterns and market conditions to create improved strategies.
         Returns the path to the generated strategy file, or None on failure.
         """
+        # Identify failure patterns first
+        patterns = self.identify_failure_patterns(failures)
+
         prompt = (
             "You are a quantitative trading strategy developer.\n"
-            "Analyze these failed trades and generate an improved strategy.\n\n"
-            f"Failed trades:\n{json.dumps(failures, indent=2, default=str)}\n\n"
-            "Generate a Python class that inherits from BaseStrategy.\n"
-            "The class must have an `evaluate(self, market_data: dict) -> dict` method.\n"
+            "Analyze these failed trades and their patterns, then generate an improved strategy.\n\n"
+            f"Failure Patterns:\n{json.dumps(patterns, indent=2)}\n\n"
+            f"Sample Failed Trades (first 5):\n"
+            f"{json.dumps(failures[:5], indent=2, default=str)}\n\n"
+            "Based on these patterns, generate an improved trading strategy.\n"
+            "The strategy should:\n"
+            "1. Avoid the identified failure patterns\n"
+            "2. Consider market-specific conditions\n"
+            "3. Adjust confidence based on historical performance\n\n"
+            "Generate a Python method body that inherits from BaseStrategy.\n"
+            "The method signature is: evaluate(self, market_data: dict) -> dict\n"
             "The method must return a dict with keys: action, confidence, rationale.\n"
             "Respond with ONLY the method body (Python code), no class definition.\n"
         )
@@ -147,10 +237,15 @@ class EvolutionOptimizer:
         # Indent the body for the class method
         indented_body = textwrap.indent(body, "            ")
 
+        # Generate rationale from patterns
+        rationale = f"Auto-evolved from {len(failures)} failures. "
+        rationale += f"Primary failure markets: {list(patterns.get('markets', {}).keys())}. "
+        rationale += f"Average loss: {patterns.get('avg_loss', 0.0)}"
+
         content = STRATEGY_TEMPLATE.format(
             name=version,
             timestamp=datetime.now(UTC).isoformat(),
-            rationale="Auto-evolved from failure analysis",
+            rationale=rationale,
             class_name=class_name,
             body=indented_body.strip(),
         )

src/evolution/performance_tracker.py

@@ -0,0 +1,303 @@
+"""Performance tracking system for strategy monitoring.
+
+Tracks win rates, monitors improvement over time,
+and provides performance metrics dashboard.
+"""
+
+from __future__ import annotations
+
+import json
+import logging
+import sqlite3
+from dataclasses import asdict, dataclass
+from datetime import UTC, datetime, timedelta
+from typing import Any
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class StrategyMetrics:
+    """Performance metrics for a strategy over a time period."""
+
+    strategy_name: str
+    period_start: str
+    period_end: str
+    total_trades: int
+    wins: int
+    losses: int
+    holds: int
+    win_rate: float
+    avg_pnl: float
+    total_pnl: float
+    best_trade: float
+    worst_trade: float
+    avg_confidence: float
+
+
+@dataclass
+class PerformanceDashboard:
+    """Comprehensive performance dashboard."""
+
+    generated_at: str
+    overall_metrics: StrategyMetrics
+    daily_metrics: list[StrategyMetrics]
+    weekly_metrics: list[StrategyMetrics]
+    improvement_trend: dict[str, Any]
+
+
+class PerformanceTracker:
+    """Tracks and monitors strategy performance over time."""
+
+    def __init__(self, db_path: str) -> None:
+        """Initialize performance tracker.
+
+        Args:
+            db_path: Path to the trade logs database
+        """
+        self._db_path = db_path
+
+    def get_strategy_metrics(
+        self,
+        strategy_name: str | None = None,
+        start_date: str | None = None,
+        end_date: str | None = None,
+    ) -> StrategyMetrics:
+        """Get performance metrics for a strategy over a time period.
+
+        Args:
+            strategy_name: Name of the strategy (None = all strategies)
+            start_date: Start date in ISO format (None = beginning of time)
+            end_date: End date in ISO format (None = now)
+
+        Returns:
+            StrategyMetrics object with performance data
+        """
+        conn = sqlite3.connect(self._db_path)
+        conn.row_factory = sqlite3.Row
+
+        try:
+            # Build query with optional filters
+            query = """
+                SELECT
+                    COUNT(*) as total_trades,
+                    SUM(CASE WHEN pnl > 0 THEN 1 ELSE 0 END) as wins,
+                    SUM(CASE WHEN pnl < 0 THEN 1 ELSE 0 END) as losses,
+                    SUM(CASE WHEN action = 'HOLD' THEN 1 ELSE 0 END) as holds,
+                    COALESCE(AVG(CASE WHEN pnl IS NOT NULL THEN pnl END), 0) as avg_pnl,
+                    COALESCE(SUM(CASE WHEN pnl IS NOT NULL THEN pnl ELSE 0 END), 0) as total_pnl,
+                    COALESCE(MAX(pnl), 0) as best_trade,
+                    COALESCE(MIN(pnl), 0) as worst_trade,
+                    COALESCE(AVG(confidence), 0) as avg_confidence,
+                    MIN(timestamp) as period_start,
+                    MAX(timestamp) as period_end
+                FROM trades
+                WHERE 1=1
+            """
+            params: list[Any] = []
+
+            if start_date:
+                query += " AND timestamp >= ?"
+                params.append(start_date)
+
+            if end_date:
+                query += " AND timestamp <= ?"
+                params.append(end_date)
+
+            # Note: Currently trades table doesn't have strategy_name column
+            # This is a placeholder for future extension
+
+            row = conn.execute(query, params).fetchone()
+
+            total_trades = row["total_trades"] or 0
+            wins = row["wins"] or 0
+            win_rate = (wins / total_trades * 100) if total_trades > 0 else 0.0
+
+            return StrategyMetrics(
+                strategy_name=strategy_name or "default",
+                period_start=row["period_start"] or "",
+                period_end=row["period_end"] or "",
+                total_trades=total_trades,
+                wins=wins,
+                losses=row["losses"] or 0,
+                holds=row["holds"] or 0,
+                win_rate=round(win_rate, 2),
+                avg_pnl=round(row["avg_pnl"], 2),
+                total_pnl=round(row["total_pnl"], 2),
+                best_trade=round(row["best_trade"], 2),
+                worst_trade=round(row["worst_trade"], 2),
+                avg_confidence=round(row["avg_confidence"], 2),
+            )
+        finally:
+            conn.close()
+
+    def get_daily_metrics(
+        self, days: int = 7, strategy_name: str | None = None
+    ) -> list[StrategyMetrics]:
+        """Get daily performance metrics for the last N days.
+
+        Args:
+            days: Number of days to retrieve (default 7)
+            strategy_name: Name of the strategy (None = all strategies)
+
+        Returns:
+            List of StrategyMetrics, one per day
+        """
+        metrics = []
+        end_date = datetime.now(UTC)
+
+        for i in range(days):
+            day_end = end_date - timedelta(days=i)
+            day_start = day_end - timedelta(days=1)
+
+            day_metrics = self.get_strategy_metrics(
+                strategy_name=strategy_name,
+                start_date=day_start.isoformat(),
+                end_date=day_end.isoformat(),
+            )
+            metrics.append(day_metrics)
+
+        return metrics
+
+    def get_weekly_metrics(
+        self, weeks: int = 4, strategy_name: str | None = None
+    ) -> list[StrategyMetrics]:
+        """Get weekly performance metrics for the last N weeks.
+
+        Args:
+            weeks: Number of weeks to retrieve (default 4)
+            strategy_name: Name of the strategy (None = all strategies)
+
+        Returns:
+            List of StrategyMetrics, one per week
+        """
+        metrics = []
+        end_date = datetime.now(UTC)
+
+        for i in range(weeks):
+            week_end = end_date - timedelta(weeks=i)
+            week_start = week_end - timedelta(weeks=1)
+
+            week_metrics = self.get_strategy_metrics(
+                strategy_name=strategy_name,
+                start_date=week_start.isoformat(),
+                end_date=week_end.isoformat(),
+            )
+            metrics.append(week_metrics)
+
+        return metrics
+
+    def calculate_improvement_trend(
+        self, metrics_history: list[StrategyMetrics]
+    ) -> dict[str, Any]:
+        """Calculate improvement trend from historical metrics.
+
+        Args:
+            metrics_history: List of StrategyMetrics ordered from oldest to newest
+
+        Returns:
+            Dictionary with trend analysis
+        """
+        if len(metrics_history) < 2:
+            return {
+                "trend": "insufficient_data",
+                "win_rate_change": 0.0,
+                "pnl_change": 0.0,
+                "confidence_change": 0.0,
+            }
+
+        oldest = metrics_history[0]
+        newest = metrics_history[-1]
+
+        win_rate_change = newest.win_rate - oldest.win_rate
+        pnl_change = newest.avg_pnl - oldest.avg_pnl
+        confidence_change = newest.avg_confidence - oldest.avg_confidence
+
+        # Determine overall trend
+        if win_rate_change > 5.0 and pnl_change > 0:
+            trend = "improving"
+        elif win_rate_change < -5.0 or pnl_change < 0:
+            trend = "declining"
+        else:
+            trend = "stable"
+
+        return {
+            "trend": trend,
+            "win_rate_change": round(win_rate_change, 2),
+            "pnl_change": round(pnl_change, 2),
+            "confidence_change": round(confidence_change, 2),
+            "period_count": len(metrics_history),
+        }
+
+    def generate_dashboard(
+        self, strategy_name: str | None = None
+    ) -> PerformanceDashboard:
+        """Generate a comprehensive performance dashboard.
+
+        Args:
+            strategy_name: Name of the strategy (None = all strategies)
+
+        Returns:
+            PerformanceDashboard with all metrics
+        """
+        # Get overall metrics
+        overall_metrics = self.get_strategy_metrics(strategy_name=strategy_name)
+
+        # Get daily metrics (last 7 days)
+        daily_metrics = self.get_daily_metrics(days=7, strategy_name=strategy_name)
+
+        # Get weekly metrics (last 4 weeks)
+        weekly_metrics = self.get_weekly_metrics(weeks=4, strategy_name=strategy_name)
+
+        # Calculate improvement trend
+        improvement_trend = self.calculate_improvement_trend(weekly_metrics[::-1])
+
+        return PerformanceDashboard(
+            generated_at=datetime.now(UTC).isoformat(),
+            overall_metrics=overall_metrics,
+            daily_metrics=daily_metrics,
+            weekly_metrics=weekly_metrics,
+            improvement_trend=improvement_trend,
+        )
+
+    def export_dashboard_json(
+        self, dashboard: PerformanceDashboard
+    ) -> str:
+        """Export dashboard as JSON string.
+
+        Args:
+            dashboard: PerformanceDashboard object
+
+        Returns:
+            JSON string representation
+        """
+        data = {
+            "generated_at": dashboard.generated_at,
+            "overall_metrics": asdict(dashboard.overall_metrics),
+            "daily_metrics": [asdict(m) for m in dashboard.daily_metrics],
+            "weekly_metrics": [asdict(m) for m in dashboard.weekly_metrics],
+            "improvement_trend": dashboard.improvement_trend,
+        }
+        return json.dumps(data, indent=2)
+
+    def log_dashboard(self, dashboard: PerformanceDashboard) -> None:
+        """Log dashboard summary to logger.
+
+        Args:
+            dashboard: PerformanceDashboard object
+        """
+        logger.info("=" * 60)
+        logger.info("PERFORMANCE DASHBOARD")
+        logger.info("=" * 60)
+        logger.info("Generated: %s", dashboard.generated_at)
+        logger.info("")
+        logger.info("Overall Performance:")
+        logger.info("  Total Trades: %d", dashboard.overall_metrics.total_trades)
+        logger.info("  Win Rate: %.2f%%", dashboard.overall_metrics.win_rate)
+        logger.info("  Average P&L: %.2f", dashboard.overall_metrics.avg_pnl)
+        logger.info("  Total P&L: %.2f", dashboard.overall_metrics.total_pnl)
+        logger.info("")
+        logger.info("Improvement Trend (%s):", dashboard.improvement_trend["trend"])
+        logger.info("  Win Rate Change: %+.2f%%", dashboard.improvement_trend["win_rate_change"])
+        logger.info("  P&L Change: %+.2f", dashboard.improvement_trend["pnl_change"])
+        logger.info("=" * 60)

src/logging/__init__.py

@@ -0,0 +1,5 @@
+"""Decision logging and audit trail for trade decisions."""
+
+from src.logging.decision_logger import DecisionLog, DecisionLogger
+
+__all__ = ["DecisionLog", "DecisionLogger"]

src/logging/decision_logger.py

@@ -0,0 +1,235 @@
+"""Decision logging system with context snapshots for comprehensive audit trail."""
+
+from __future__ import annotations
+
+import json
+import sqlite3
+import uuid
+from dataclasses import dataclass
+from datetime import UTC, datetime
+from typing import Any
+
+
+@dataclass
+class DecisionLog:
+    """A logged trading decision with context and outcome."""
+
+    decision_id: str
+    timestamp: str
+    stock_code: str
+    market: str
+    exchange_code: str
+    action: str
+    confidence: int
+    rationale: str
+    context_snapshot: dict[str, Any]
+    input_data: dict[str, Any]
+    outcome_pnl: float | None = None
+    outcome_accuracy: int | None = None
+    reviewed: bool = False
+    review_notes: str | None = None
+
+
+class DecisionLogger:
+    """Logs trading decisions with full context for review and evolution."""
+
+    def __init__(self, conn: sqlite3.Connection) -> None:
+        """Initialize the decision logger with a database connection."""
+        self.conn = conn
+
+    def log_decision(
+        self,
+        stock_code: str,
+        market: str,
+        exchange_code: str,
+        action: str,
+        confidence: int,
+        rationale: str,
+        context_snapshot: dict[str, Any],
+        input_data: dict[str, Any],
+    ) -> str:
+        """Log a trading decision with full context.
+
+        Args:
+            stock_code: Stock symbol
+            market: Market code (e.g., "KR", "US_NASDAQ")
+            exchange_code: Exchange code (e.g., "KRX", "NASDAQ")
+            action: Trading action (BUY/SELL/HOLD)
+            confidence: Confidence level (0-100)
+            rationale: Reasoning for the decision
+            context_snapshot: L1-L7 context snapshot at decision time
+            input_data: Market data inputs (price, volume, orderbook, etc.)
+
+        Returns:
+            decision_id: Unique identifier for this decision
+        """
+        decision_id = str(uuid.uuid4())
+        timestamp = datetime.now(UTC).isoformat()
+
+        self.conn.execute(
+            """
+            INSERT INTO decision_logs (
+                decision_id, timestamp, stock_code, market, exchange_code,
+                action, confidence, rationale, context_snapshot, input_data
+            )
+            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+            """,
+            (
+                decision_id,
+                timestamp,
+                stock_code,
+                market,
+                exchange_code,
+                action,
+                confidence,
+                rationale,
+                json.dumps(context_snapshot),
+                json.dumps(input_data),
+            ),
+        )
+        self.conn.commit()
+
+        return decision_id
+
+    def get_unreviewed_decisions(
+        self, min_confidence: int = 80, limit: int | None = None
+    ) -> list[DecisionLog]:
+        """Get unreviewed decisions with high confidence.
+
+        Args:
+            min_confidence: Minimum confidence threshold (default 80)
+            limit: Maximum number of results (None = unlimited)
+
+        Returns:
+            List of unreviewed DecisionLog objects
+        """
+        query = """
+            SELECT
+                decision_id, timestamp, stock_code, market, exchange_code,
+                action, confidence, rationale, context_snapshot, input_data,
+                outcome_pnl, outcome_accuracy, reviewed, review_notes
+            FROM decision_logs
+            WHERE reviewed = 0 AND confidence >= ?
+            ORDER BY timestamp DESC
+        """
+        if limit is not None:
+            query += f" LIMIT {limit}"
+
+        cursor = self.conn.execute(query, (min_confidence,))
+        return [self._row_to_decision_log(row) for row in cursor.fetchall()]
+
+    def mark_reviewed(self, decision_id: str, notes: str) -> None:
+        """Mark a decision as reviewed with notes.
+
+        Args:
+            decision_id: Decision identifier
+            notes: Review notes and insights
+        """
+        self.conn.execute(
+            """
+            UPDATE decision_logs
+            SET reviewed = 1, review_notes = ?
+            WHERE decision_id = ?
+            """,
+            (notes, decision_id),
+        )
+        self.conn.commit()
+
+    def update_outcome(
+        self, decision_id: str, pnl: float, accuracy: int
+    ) -> None:
+        """Update the outcome of a decision after trade execution.
+
+        Args:
+            decision_id: Decision identifier
+            pnl: Actual profit/loss realized
+            accuracy: 1 if decision was correct, 0 if wrong
+        """
+        self.conn.execute(
+            """
+            UPDATE decision_logs
+            SET outcome_pnl = ?, outcome_accuracy = ?
+            WHERE decision_id = ?
+            """,
+            (pnl, accuracy, decision_id),
+        )
+        self.conn.commit()
+
+    def get_decision_by_id(self, decision_id: str) -> DecisionLog | None:
+        """Get a specific decision by ID.
+
+        Args:
+            decision_id: Decision identifier
+
+        Returns:
+            DecisionLog object or None if not found
+        """
+        cursor = self.conn.execute(
+            """
+            SELECT
+                decision_id, timestamp, stock_code, market, exchange_code,
+                action, confidence, rationale, context_snapshot, input_data,
+                outcome_pnl, outcome_accuracy, reviewed, review_notes
+            FROM decision_logs
+            WHERE decision_id = ?
+            """,
+            (decision_id,),
+        )
+        row = cursor.fetchone()
+        return self._row_to_decision_log(row) if row else None
+
+    def get_losing_decisions(
+        self, min_confidence: int = 80, min_loss: float = -100.0
+    ) -> list[DecisionLog]:
+        """Get high-confidence decisions that resulted in losses.
+
+        Useful for identifying patterns in failed predictions.
+
+        Args:
+            min_confidence: Minimum confidence threshold (default 80)
+            min_loss: Minimum loss amount (default -100.0, i.e., loss >= 100)
+
+        Returns:
+            List of losing DecisionLog objects
+        """
+        cursor = self.conn.execute(
+            """
+            SELECT
+                decision_id, timestamp, stock_code, market, exchange_code,
+                action, confidence, rationale, context_snapshot, input_data,
+                outcome_pnl, outcome_accuracy, reviewed, review_notes
+            FROM decision_logs
+            WHERE confidence >= ?
+              AND outcome_pnl IS NOT NULL
+              AND outcome_pnl <= ?
+            ORDER BY outcome_pnl ASC
+            """,
+            (min_confidence, min_loss),
+        )
+        return [self._row_to_decision_log(row) for row in cursor.fetchall()]
+
+    def _row_to_decision_log(self, row: tuple[Any, ...]) -> DecisionLog:
+        """Convert a database row to a DecisionLog object.
+
+        Args:
+            row: Database row tuple
+
+        Returns:
+            DecisionLog object
+        """
+        return DecisionLog(
+            decision_id=row[0],
+            timestamp=row[1],
+            stock_code=row[2],
+            market=row[3],
+            exchange_code=row[4],
+            action=row[5],
+            confidence=row[6],
+            rationale=row[7],
+            context_snapshot=json.loads(row[8]),
+            input_data=json.loads(row[9]),
+            outcome_pnl=row[10],
+            outcome_accuracy=row[11],
+            reviewed=bool(row[12]),
+            review_notes=row[13],
+        )

src/main.py

@@ -13,12 +13,19 @@ import signal
 from datetime import UTC, datetime
 from typing import Any
 
+from src.analysis.scanner import MarketScanner
+from src.analysis.volatility import VolatilityAnalyzer
 from src.brain.gemini_client import GeminiClient
 from src.broker.kis_api import KISBroker
 from src.broker.overseas import OverseasBroker
 from src.config import Settings
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+from src.core.criticality import CriticalityAssessor
+from src.core.priority_queue import PriorityTaskQueue
 from src.core.risk_manager import CircuitBreakerTripped, RiskManager
 from src.db import init_db, log_trade
+from src.logging.decision_logger import DecisionLogger
 from src.logging_config import setup_logging
 from src.markets.schedule import MarketInfo, get_next_market_open, get_open_markets
 
@@ -33,8 +40,18 @@ WATCHLISTS = {
 }
 
 TRADE_INTERVAL_SECONDS = 60
+SCAN_INTERVAL_SECONDS = 60  # Scan markets every 60 seconds
 MAX_CONNECTION_RETRIES = 3
 
+# Full stock universe per market (for scanning)
+# In production, this would be loaded from a database or API
+STOCK_UNIVERSE = {
+    "KR": ["005930", "000660", "035420", "051910", "005380", "005490"],
+    "US_NASDAQ": ["AAPL", "MSFT", "GOOGL", "AMZN", "NVDA", "TSLA"],
+    "US_NYSE": ["JPM", "BAC", "XOM", "JNJ", "V"],
+    "JP": ["7203", "6758", "9984", "6861"],
+}
+
 
 async def trading_cycle(
     broker: KISBroker,
@@ -42,10 +59,15 @@ async def trading_cycle(
     brain: GeminiClient,
     risk: RiskManager,
     db_conn: Any,
+    decision_logger: DecisionLogger,
+    context_store: ContextStore,
+    criticality_assessor: CriticalityAssessor,
     market: MarketInfo,
     stock_code: str,
 ) -> None:
     """Execute one trading cycle for a single stock."""
+    cycle_start_time = asyncio.get_event_loop().time()
+
     # 1. Fetch market data
     if market.is_domestic:
         orderbook = await broker.get_orderbook(stock_code)
@@ -91,6 +113,42 @@ async def trading_cycle(
         "foreigner_net": foreigner_net,
     }
 
+    # 1.5. Get volatility metrics from context store (L7_REALTIME)
+    latest_timeframe = context_store.get_latest_timeframe(ContextLayer.L7_REALTIME)
+    volatility_score = 50.0  # Default normal volatility
+    volume_surge = 1.0
+    price_change_1m = 0.0
+
+    if latest_timeframe:
+        volatility_data = context_store.get_context(
+            ContextLayer.L7_REALTIME,
+            latest_timeframe,
+            f"volatility_{stock_code}",
+        )
+        if volatility_data:
+            volatility_score = volatility_data.get("momentum_score", 50.0)
+            volume_surge = volatility_data.get("volume_surge", 1.0)
+            price_change_1m = volatility_data.get("price_change_1m", 0.0)
+
+    # 1.6. Assess criticality based on market conditions
+    criticality = criticality_assessor.assess_market_conditions(
+        pnl_pct=pnl_pct,
+        volatility_score=volatility_score,
+        volume_surge=volume_surge,
+        price_change_1m=price_change_1m,
+        is_market_open=True,
+    )
+
+    logger.info(
+        "Criticality for %s (%s): %s (pnl=%.2f%%, volatility=%.1f, volume_surge=%.1fx)",
+        stock_code,
+        market.name,
+        criticality.value,
+        pnl_pct,
+        volatility_score,
+        volume_surge,
+    )
+
     # 2. Ask the brain for a decision
     decision = await brain.decide(market_data)
     logger.info(
@@ -101,6 +159,39 @@ async def trading_cycle(
         decision.confidence,
     )
 
+    # 2.5. Log decision with context snapshot
+    context_snapshot = {
+        "L1": {
+            "current_price": current_price,
+            "foreigner_net": foreigner_net,
+        },
+        "L2": {
+            "total_eval": total_eval,
+            "total_cash": total_cash,
+            "purchase_total": purchase_total,
+            "pnl_pct": pnl_pct,
+        },
+        # L3-L7 will be populated when context tree is implemented
+    }
+    input_data = {
+        "current_price": current_price,
+        "foreigner_net": foreigner_net,
+        "total_eval": total_eval,
+        "total_cash": total_cash,
+        "pnl_pct": pnl_pct,
+    }
+
+    decision_logger.log_decision(
+        stock_code=stock_code,
+        market=market.code,
+        exchange_code=market.exchange_code,
+        action=decision.action,
+        confidence=decision.confidence,
+        rationale=decision.rationale,
+        context_snapshot=context_snapshot,
+        input_data=input_data,
+    )
+
     # 3. Execute if actionable
     if decision.action in ("BUY", "SELL"):
         # Determine order size (simplified: 1 lot)
@@ -143,6 +234,27 @@ async def trading_cycle(
         exchange_code=market.exchange_code,
     )
 
+    # 7. Latency monitoring
+    cycle_end_time = asyncio.get_event_loop().time()
+    cycle_latency = cycle_end_time - cycle_start_time
+    timeout = criticality_assessor.get_timeout(criticality)
+
+    if timeout and cycle_latency > timeout:
+        logger.warning(
+            "Trading cycle exceeded timeout for %s (criticality=%s, latency=%.2fs, timeout=%.2fs)",
+            stock_code,
+            criticality.value,
+            cycle_latency,
+            timeout,
+        )
+    else:
+        logger.debug(
+            "Trading cycle completed within timeout for %s (criticality=%s, latency=%.2fs)",
+            stock_code,
+            criticality.value,
+            cycle_latency,
+        )
+
 
 async def run(settings: Settings) -> None:
     """Main async loop — iterate over open markets on a timer."""
@@ -151,6 +263,31 @@ async def run(settings: Settings) -> None:
     brain = GeminiClient(settings)
     risk = RiskManager(settings)
     db_conn = init_db(settings.DB_PATH)
+    decision_logger = DecisionLogger(db_conn)
+    context_store = ContextStore(db_conn)
+
+    # Initialize volatility hunter
+    volatility_analyzer = VolatilityAnalyzer(min_volume_surge=2.0, min_price_change=1.0)
+    market_scanner = MarketScanner(
+        broker=broker,
+        overseas_broker=overseas_broker,
+        volatility_analyzer=volatility_analyzer,
+        context_store=context_store,
+        top_n=5,
+    )
+
+    # Initialize latency control system
+    criticality_assessor = CriticalityAssessor(
+        critical_pnl_threshold=-2.5,  # Near circuit breaker at -3.0%
+        critical_price_change_threshold=5.0,  # 5% in 1 minute
+        critical_volume_surge_threshold=10.0,  # 10x average
+        high_volatility_threshold=70.0,
+        low_volatility_threshold=30.0,
+    )
+    priority_queue = PriorityTaskQueue(max_size=1000)
+
+    # Track last scan time for each market
+    last_scan_time: dict[str, float] = {}
 
     shutdown = asyncio.Event()
 
@@ -196,6 +333,39 @@ async def run(settings: Settings) -> None:
                 if shutdown.is_set():
                     break
 
+                # Volatility Hunter: Scan market periodically to update watchlist
+                now_timestamp = asyncio.get_event_loop().time()
+                last_scan = last_scan_time.get(market.code, 0.0)
+                if now_timestamp - last_scan >= SCAN_INTERVAL_SECONDS:
+                    try:
+                        # Scan all stocks in the universe
+                        stock_universe = STOCK_UNIVERSE.get(market.code, [])
+                        if stock_universe:
+                            logger.info("Volatility Hunter: Scanning %s market", market.name)
+                            scan_result = await market_scanner.scan_market(
+                                market, stock_universe
+                            )
+
+                            # Update watchlist with top movers
+                            current_watchlist = WATCHLISTS.get(market.code, [])
+                            updated_watchlist = market_scanner.get_updated_watchlist(
+                                current_watchlist,
+                                scan_result,
+                                max_replacements=2,
+                            )
+                            WATCHLISTS[market.code] = updated_watchlist
+
+                            logger.info(
+                                "Volatility Hunter: Watchlist updated for %s (%d top movers, %d breakouts)",
+                                market.name,
+                                len(scan_result.top_movers),
+                                len(scan_result.breakouts),
+                            )
+
+                        last_scan_time[market.code] = now_timestamp
+                    except Exception as exc:
+                        logger.error("Volatility Hunter scan failed for %s: %s", market.name, exc)
+
                 # Get watchlist for this market
                 watchlist = WATCHLISTS.get(market.code, [])
                 if not watchlist:
@@ -218,6 +388,9 @@ async def run(settings: Settings) -> None:
                                 brain,
                                 risk,
                                 db_conn,
+                                decision_logger,
+                                context_store,
+                                criticality_assessor,
                                 market,
                                 stock_code,
                             )
@@ -246,6 +419,18 @@ async def run(settings: Settings) -> None:
                             logger.exception("Unexpected error for %s: %s", stock_code, exc)
                             break  # Don't retry on unexpected errors
 
+            # Log priority queue metrics periodically
+            metrics = await priority_queue.get_metrics()
+            if metrics.total_enqueued > 0:
+                logger.info(
+                    "Priority queue metrics: enqueued=%d, dequeued=%d, size=%d, timeouts=%d, errors=%d",
+                    metrics.total_enqueued,
+                    metrics.total_dequeued,
+                    metrics.current_size,
+                    metrics.total_timeouts,
+                    metrics.total_errors,
+                )
+
             # Wait for next cycle or shutdown
             try:
                 await asyncio.wait_for(shutdown.wait(), timeout=TRADE_INTERVAL_SECONDS)

tests/test_context.py

@@ -0,0 +1,350 @@
+"""Tests for the multi-layered context management system."""
+
+from __future__ import annotations
+
+import sqlite3
+from datetime import UTC, datetime, timedelta
+
+import pytest
+
+from src.context.aggregator import ContextAggregator
+from src.context.layer import LAYER_CONFIG, ContextLayer
+from src.context.store import ContextStore
+from src.db import init_db, log_trade
+
+
+@pytest.fixture
+def db_conn() -> sqlite3.Connection:
+    """Provide an in-memory database connection."""
+    return init_db(":memory:")
+
+
+@pytest.fixture
+def store(db_conn: sqlite3.Connection) -> ContextStore:
+    """Provide a ContextStore instance."""
+    return ContextStore(db_conn)
+
+
+@pytest.fixture
+def aggregator(db_conn: sqlite3.Connection) -> ContextAggregator:
+    """Provide a ContextAggregator instance."""
+    return ContextAggregator(db_conn)
+
+
+class TestContextStore:
+    """Test suite for ContextStore CRUD operations."""
+
+    def test_set_and_get_context(self, store: ContextStore) -> None:
+        """Test setting and retrieving a context value."""
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl", 1234.56)
+
+        value = store.get_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl")
+        assert value == 1234.56
+
+    def test_get_nonexistent_context(self, store: ContextStore) -> None:
+        """Test retrieving a non-existent context returns None."""
+        value = store.get_context(ContextLayer.L6_DAILY, "2026-02-04", "nonexistent")
+        assert value is None
+
+    def test_update_existing_context(self, store: ContextStore) -> None:
+        """Test updating an existing context value."""
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl", 100.0)
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl", 200.0)
+
+        value = store.get_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl")
+        assert value == 200.0
+
+    def test_get_all_contexts_for_layer(self, store: ContextStore) -> None:
+        """Test retrieving all contexts for a specific layer."""
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "total_pnl", 100.0)
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "trade_count", 10)
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "win_rate", 60.5)
+
+        contexts = store.get_all_contexts(ContextLayer.L6_DAILY, "2026-02-04")
+        assert len(contexts) == 3
+        assert contexts["total_pnl"] == 100.0
+        assert contexts["trade_count"] == 10
+        assert contexts["win_rate"] == 60.5
+
+    def test_get_latest_timeframe(self, store: ContextStore) -> None:
+        """Test getting the most recent timeframe for a layer."""
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-01", "total_pnl", 100.0)
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-03", "total_pnl", 200.0)
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-02", "total_pnl", 150.0)
+
+        latest = store.get_latest_timeframe(ContextLayer.L6_DAILY)
+        # Latest by updated_at, which should be the last one set
+        assert latest == "2026-02-02"
+
+    def test_delete_old_contexts(
+        self, store: ContextStore, db_conn: sqlite3.Connection
+    ) -> None:
+        """Test deleting contexts older than a cutoff date."""
+        # Insert contexts with specific old timestamps
+        # (bypassing set_context which uses current time)
+        old_date = "2026-01-01T00:00:00+00:00"
+        new_date = "2026-02-01T00:00:00+00:00"
+
+        db_conn.execute(
+            """
+            INSERT INTO contexts (layer, timeframe, key, value, created_at, updated_at)
+            VALUES (?, ?, ?, ?, ?, ?)
+            """,
+            (ContextLayer.L6_DAILY.value, "2026-01-01", "total_pnl", "100.0", old_date, old_date),
+        )
+        db_conn.execute(
+            """
+            INSERT INTO contexts (layer, timeframe, key, value, created_at, updated_at)
+            VALUES (?, ?, ?, ?, ?, ?)
+            """,
+            (ContextLayer.L6_DAILY.value, "2026-02-01", "total_pnl", "200.0", new_date, new_date),
+        )
+        db_conn.commit()
+
+        # Delete contexts before 2026-01-15
+        cutoff = "2026-01-15T00:00:00+00:00"
+        deleted = store.delete_old_contexts(ContextLayer.L6_DAILY, cutoff)
+
+        # Should delete the 2026-01-01 context
+        assert deleted == 1
+        assert store.get_context(ContextLayer.L6_DAILY, "2026-02-01", "total_pnl") == 200.0
+        assert store.get_context(ContextLayer.L6_DAILY, "2026-01-01", "total_pnl") is None
+
+    def test_cleanup_expired_contexts(
+        self, store: ContextStore, db_conn: sqlite3.Connection
+    ) -> None:
+        """Test automatic cleanup based on retention policies."""
+        # Set old contexts for L7 (7 day retention)
+        old_date = (datetime.now(UTC) - timedelta(days=10)).isoformat()
+        db_conn.execute(
+            """
+            INSERT INTO contexts (layer, timeframe, key, value, created_at, updated_at)
+            VALUES (?, ?, ?, ?, ?, ?)
+            """,
+            (ContextLayer.L7_REALTIME.value, "2026-01-01", "price", "100.0", old_date, old_date),
+        )
+        db_conn.commit()
+
+        deleted_counts = store.cleanup_expired_contexts()
+
+        # Should delete the old L7 context (10 days > 7 day retention)
+        assert deleted_counts[ContextLayer.L7_REALTIME] == 1
+
+        # L1 has no retention limit, so nothing should be deleted
+        assert deleted_counts[ContextLayer.L1_LEGACY] == 0
+
+    def test_context_metadata_initialized(
+        self, store: ContextStore, db_conn: sqlite3.Connection
+    ) -> None:
+        """Test that context metadata is properly initialized."""
+        cursor = db_conn.execute("SELECT COUNT(*) FROM context_metadata")
+        count = cursor.fetchone()[0]
+
+        # Should have metadata for all 7 layers
+        assert count == 7
+
+        # Verify L1 metadata
+        cursor = db_conn.execute(
+            "SELECT description, retention_days FROM context_metadata WHERE layer = ?",
+            (ContextLayer.L1_LEGACY.value,),
+        )
+        row = cursor.fetchone()
+        assert row is not None
+        assert "Cumulative trading history" in row[0]
+        assert row[1] is None  # No retention limit for L1
+
+
+class TestContextAggregator:
+    """Test suite for ContextAggregator."""
+
+    def test_aggregate_daily_from_trades(
+        self, aggregator: ContextAggregator, db_conn: sqlite3.Connection
+    ) -> None:
+        """Test aggregating daily metrics from trades."""
+        date = "2026-02-04"
+
+        # Create sample trades
+        log_trade(db_conn, "005930", "BUY", 85, "Good signal", quantity=10, price=70000, pnl=500)
+        log_trade(db_conn, "000660", "SELL", 90, "Take profit", quantity=5, price=50000, pnl=1500)
+        log_trade(db_conn, "035720", "HOLD", 75, "Wait", quantity=0, price=0, pnl=0)
+
+        # Manually set timestamps to the target date
+        db_conn.execute(
+            f"UPDATE trades SET timestamp = '{date}T10:00:00+00:00'"
+        )
+        db_conn.commit()
+
+        # Aggregate
+        aggregator.aggregate_daily_from_trades(date)
+
+        # Verify L6 contexts
+        store = aggregator.store
+        assert store.get_context(ContextLayer.L6_DAILY, date, "trade_count") == 3
+        assert store.get_context(ContextLayer.L6_DAILY, date, "buys") == 1
+        assert store.get_context(ContextLayer.L6_DAILY, date, "sells") == 1
+        assert store.get_context(ContextLayer.L6_DAILY, date, "holds") == 1
+        assert store.get_context(ContextLayer.L6_DAILY, date, "total_pnl") == 2000.0
+        assert store.get_context(ContextLayer.L6_DAILY, date, "unique_stocks") == 3
+        # 2 wins, 0 losses
+        assert store.get_context(ContextLayer.L6_DAILY, date, "win_rate") == 100.0
+
+    def test_aggregate_weekly_from_daily(self, aggregator: ContextAggregator) -> None:
+        """Test aggregating weekly metrics from daily."""
+        week = "2026-W06"
+
+        # Set daily contexts
+        aggregator.store.set_context(ContextLayer.L6_DAILY, "2026-02-02", "total_pnl", 100.0)
+        aggregator.store.set_context(ContextLayer.L6_DAILY, "2026-02-03", "total_pnl", 200.0)
+        aggregator.store.set_context(ContextLayer.L6_DAILY, "2026-02-02", "avg_confidence", 80.0)
+        aggregator.store.set_context(ContextLayer.L6_DAILY, "2026-02-03", "avg_confidence", 85.0)
+
+        # Aggregate
+        aggregator.aggregate_weekly_from_daily(week)
+
+        # Verify L5 contexts
+        store = aggregator.store
+        weekly_pnl = store.get_context(ContextLayer.L5_WEEKLY, week, "weekly_pnl")
+        avg_conf = store.get_context(ContextLayer.L5_WEEKLY, week, "avg_confidence")
+
+        assert weekly_pnl == 300.0
+        assert avg_conf == 82.5
+
+    def test_aggregate_monthly_from_weekly(self, aggregator: ContextAggregator) -> None:
+        """Test aggregating monthly metrics from weekly."""
+        month = "2026-02"
+
+        # Set weekly contexts
+        aggregator.store.set_context(ContextLayer.L5_WEEKLY, "2026-W05", "weekly_pnl", 100.0)
+        aggregator.store.set_context(ContextLayer.L5_WEEKLY, "2026-W06", "weekly_pnl", 200.0)
+        aggregator.store.set_context(ContextLayer.L5_WEEKLY, "2026-W07", "weekly_pnl", 150.0)
+
+        # Aggregate
+        aggregator.aggregate_monthly_from_weekly(month)
+
+        # Verify L4 contexts
+        store = aggregator.store
+        monthly_pnl = store.get_context(ContextLayer.L4_MONTHLY, month, "monthly_pnl")
+        assert monthly_pnl == 450.0
+
+    def test_aggregate_quarterly_from_monthly(self, aggregator: ContextAggregator) -> None:
+        """Test aggregating quarterly metrics from monthly."""
+        quarter = "2026-Q1"
+
+        # Set monthly contexts for Q1 (Jan, Feb, Mar)
+        aggregator.store.set_context(ContextLayer.L4_MONTHLY, "2026-01", "monthly_pnl", 1000.0)
+        aggregator.store.set_context(ContextLayer.L4_MONTHLY, "2026-02", "monthly_pnl", 2000.0)
+        aggregator.store.set_context(ContextLayer.L4_MONTHLY, "2026-03", "monthly_pnl", 1500.0)
+
+        # Aggregate
+        aggregator.aggregate_quarterly_from_monthly(quarter)
+
+        # Verify L3 contexts
+        store = aggregator.store
+        quarterly_pnl = store.get_context(ContextLayer.L3_QUARTERLY, quarter, "quarterly_pnl")
+        assert quarterly_pnl == 4500.0
+
+    def test_aggregate_annual_from_quarterly(self, aggregator: ContextAggregator) -> None:
+        """Test aggregating annual metrics from quarterly."""
+        year = "2026"
+
+        # Set quarterly contexts for all 4 quarters
+        aggregator.store.set_context(ContextLayer.L3_QUARTERLY, "2026-Q1", "quarterly_pnl", 4500.0)
+        aggregator.store.set_context(ContextLayer.L3_QUARTERLY, "2026-Q2", "quarterly_pnl", 5000.0)
+        aggregator.store.set_context(ContextLayer.L3_QUARTERLY, "2026-Q3", "quarterly_pnl", 4800.0)
+        aggregator.store.set_context(ContextLayer.L3_QUARTERLY, "2026-Q4", "quarterly_pnl", 5200.0)
+
+        # Aggregate
+        aggregator.aggregate_annual_from_quarterly(year)
+
+        # Verify L2 contexts
+        store = aggregator.store
+        annual_pnl = store.get_context(ContextLayer.L2_ANNUAL, year, "annual_pnl")
+        assert annual_pnl == 19500.0
+
+    def test_aggregate_legacy_from_annual(self, aggregator: ContextAggregator) -> None:
+        """Test aggregating legacy metrics from all annual data."""
+        # Set annual contexts for multiple years
+        aggregator.store.set_context(ContextLayer.L2_ANNUAL, "2024", "annual_pnl", 10000.0)
+        aggregator.store.set_context(ContextLayer.L2_ANNUAL, "2025", "annual_pnl", 15000.0)
+        aggregator.store.set_context(ContextLayer.L2_ANNUAL, "2026", "annual_pnl", 20000.0)
+
+        # Aggregate
+        aggregator.aggregate_legacy_from_annual()
+
+        # Verify L1 contexts
+        store = aggregator.store
+        total_pnl = store.get_context(ContextLayer.L1_LEGACY, "LEGACY", "total_pnl")
+        years_traded = store.get_context(ContextLayer.L1_LEGACY, "LEGACY", "years_traded")
+        avg_annual_pnl = store.get_context(ContextLayer.L1_LEGACY, "LEGACY", "avg_annual_pnl")
+
+        assert total_pnl == 45000.0
+        assert years_traded == 3
+        assert avg_annual_pnl == 15000.0
+
+    def test_run_all_aggregations(
+        self, aggregator: ContextAggregator, db_conn: sqlite3.Connection
+    ) -> None:
+        """Test running all aggregations from L7 to L1."""
+        date = "2026-02-04"
+
+        # Create sample trades
+        log_trade(db_conn, "005930", "BUY", 85, "Good signal", quantity=10, price=70000, pnl=1000)
+
+        # Set timestamp
+        db_conn.execute(f"UPDATE trades SET timestamp = '{date}T10:00:00+00:00'")
+        db_conn.commit()
+
+        # Run all aggregations
+        aggregator.run_all_aggregations()
+
+        # Verify data exists in each layer
+        store = aggregator.store
+        assert store.get_context(ContextLayer.L6_DAILY, date, "total_pnl") == 1000.0
+        current_week = datetime.now(UTC).strftime("%Y-W%V")
+        assert store.get_context(ContextLayer.L5_WEEKLY, current_week, "weekly_pnl") is not None
+        # Further layers depend on time alignment, just verify no crashes
+
+
+class TestLayerMetadata:
+    """Test suite for layer metadata configuration."""
+
+    def test_all_layers_have_metadata(self) -> None:
+        """Test that all 7 layers have metadata defined."""
+        assert len(LAYER_CONFIG) == 7
+
+        for layer in ContextLayer:
+            assert layer in LAYER_CONFIG
+
+    def test_layer_retention_policies(self) -> None:
+        """Test layer retention policies are correctly configured."""
+        # L1 should have no retention limit
+        assert LAYER_CONFIG[ContextLayer.L1_LEGACY].retention_days is None
+
+        # L7 should have the shortest retention (7 days)
+        assert LAYER_CONFIG[ContextLayer.L7_REALTIME].retention_days == 7
+
+        # L2 should have a long retention (10 years)
+        assert LAYER_CONFIG[ContextLayer.L2_ANNUAL].retention_days == 365 * 10
+
+    def test_layer_aggregation_chain(self) -> None:
+        """Test that the aggregation chain is properly configured."""
+        # L7 has no source (leaf layer)
+        assert LAYER_CONFIG[ContextLayer.L7_REALTIME].aggregation_source is None
+
+        # L6 aggregates from L7
+        assert LAYER_CONFIG[ContextLayer.L6_DAILY].aggregation_source == ContextLayer.L7_REALTIME
+
+        # L5 aggregates from L6
+        assert LAYER_CONFIG[ContextLayer.L5_WEEKLY].aggregation_source == ContextLayer.L6_DAILY
+
+        # L4 aggregates from L5
+        assert LAYER_CONFIG[ContextLayer.L4_MONTHLY].aggregation_source == ContextLayer.L5_WEEKLY
+
+        # L3 aggregates from L4
+        assert LAYER_CONFIG[ContextLayer.L3_QUARTERLY].aggregation_source == ContextLayer.L4_MONTHLY
+
+        # L2 aggregates from L3
+        assert LAYER_CONFIG[ContextLayer.L2_ANNUAL].aggregation_source == ContextLayer.L3_QUARTERLY
+
+        # L1 aggregates from L2
+        assert LAYER_CONFIG[ContextLayer.L1_LEGACY].aggregation_source == ContextLayer.L2_ANNUAL

tests/test_decision_logger.py

@@ -0,0 +1,292 @@
+"""Tests for decision logging and audit trail."""
+
+from __future__ import annotations
+
+import sqlite3
+from datetime import UTC, datetime
+
+import pytest
+
+from src.db import init_db
+from src.logging.decision_logger import DecisionLog, DecisionLogger
+
+
+@pytest.fixture
+def db_conn() -> sqlite3.Connection:
+    """Provide an in-memory database with initialized schema."""
+    conn = init_db(":memory:")
+    return conn
+
+
+@pytest.fixture
+def logger(db_conn: sqlite3.Connection) -> DecisionLogger:
+    """Provide a DecisionLogger instance."""
+    return DecisionLogger(db_conn)
+
+
+def test_log_decision_creates_record(logger: DecisionLogger, db_conn: sqlite3.Connection) -> None:
+    """Test that log_decision creates a database record."""
+    context_snapshot = {
+        "L1": {"quote": {"price": 100.0, "volume": 1000}},
+        "L2": {"orderbook": {"bid": [99.0], "ask": [101.0]}},
+    }
+    input_data = {"price": 100.0, "volume": 1000, "foreigner_net": 500}
+
+    decision_id = logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=85,
+        rationale="Strong upward momentum",
+        context_snapshot=context_snapshot,
+        input_data=input_data,
+    )
+
+    # Verify decision_id is a valid UUID
+    assert decision_id is not None
+    assert len(decision_id) == 36  # UUID v4 format
+
+    # Verify record exists in database
+    cursor = db_conn.execute(
+        "SELECT decision_id, action, confidence FROM decision_logs WHERE decision_id = ?",
+        (decision_id,),
+    )
+    row = cursor.fetchone()
+    assert row is not None
+    assert row[0] == decision_id
+    assert row[1] == "BUY"
+    assert row[2] == 85
+
+
+def test_log_decision_stores_context_snapshot(logger: DecisionLogger) -> None:
+    """Test that context snapshot is stored as JSON."""
+    context_snapshot = {
+        "L1": {"real_time": "data"},
+        "L3": {"daily": "aggregate"},
+        "L7": {"legacy": "wisdom"},
+    }
+    input_data = {"price": 50000.0, "volume": 2000}
+
+    decision_id = logger.log_decision(
+        stock_code="035420",
+        market="KR",
+        exchange_code="KRX",
+        action="HOLD",
+        confidence=75,
+        rationale="Waiting for clearer signal",
+        context_snapshot=context_snapshot,
+        input_data=input_data,
+    )
+
+    # Retrieve and verify context snapshot
+    decision = logger.get_decision_by_id(decision_id)
+    assert decision is not None
+    assert decision.context_snapshot == context_snapshot
+    assert decision.input_data == input_data
+
+
+def test_get_unreviewed_decisions(logger: DecisionLogger) -> None:
+    """Test retrieving unreviewed decisions with confidence filter."""
+    # Log multiple decisions with varying confidence
+    logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=90,
+        rationale="High confidence buy",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.log_decision(
+        stock_code="000660",
+        market="KR",
+        exchange_code="KRX",
+        action="SELL",
+        confidence=75,
+        rationale="Low confidence sell",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.log_decision(
+        stock_code="035420",
+        market="KR",
+        exchange_code="KRX",
+        action="HOLD",
+        confidence=85,
+        rationale="Medium confidence hold",
+        context_snapshot={},
+        input_data={},
+    )
+
+    # Get unreviewed decisions with default threshold (80)
+    unreviewed = logger.get_unreviewed_decisions()
+    assert len(unreviewed) == 2  # Only confidence >= 80
+    assert all(d.confidence >= 80 for d in unreviewed)
+    assert all(not d.reviewed for d in unreviewed)
+
+    # Get with lower threshold
+    unreviewed_all = logger.get_unreviewed_decisions(min_confidence=70)
+    assert len(unreviewed_all) == 3
+
+
+def test_mark_reviewed(logger: DecisionLogger) -> None:
+    """Test marking a decision as reviewed."""
+    decision_id = logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=85,
+        rationale="Test decision",
+        context_snapshot={},
+        input_data={},
+    )
+
+    # Initially unreviewed
+    decision = logger.get_decision_by_id(decision_id)
+    assert decision is not None
+    assert not decision.reviewed
+    assert decision.review_notes is None
+
+    # Mark as reviewed
+    review_notes = "Good decision, captured bullish momentum correctly"
+    logger.mark_reviewed(decision_id, review_notes)
+
+    # Verify updated
+    decision = logger.get_decision_by_id(decision_id)
+    assert decision is not None
+    assert decision.reviewed
+    assert decision.review_notes == review_notes
+
+    # Should not appear in unreviewed list
+    unreviewed = logger.get_unreviewed_decisions()
+    assert all(d.decision_id != decision_id for d in unreviewed)
+
+
+def test_update_outcome(logger: DecisionLogger) -> None:
+    """Test updating decision outcome with P&L and accuracy."""
+    decision_id = logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=90,
+        rationale="Expecting price increase",
+        context_snapshot={},
+        input_data={},
+    )
+
+    # Initially no outcome
+    decision = logger.get_decision_by_id(decision_id)
+    assert decision is not None
+    assert decision.outcome_pnl is None
+    assert decision.outcome_accuracy is None
+
+    # Update outcome (profitable trade)
+    logger.update_outcome(decision_id, pnl=5000.0, accuracy=1)
+
+    # Verify updated
+    decision = logger.get_decision_by_id(decision_id)
+    assert decision is not None
+    assert decision.outcome_pnl == 5000.0
+    assert decision.outcome_accuracy == 1
+
+
+def test_get_losing_decisions(logger: DecisionLogger) -> None:
+    """Test retrieving high-confidence losing decisions."""
+    # Profitable decision
+    id1 = logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=85,
+        rationale="Correct prediction",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.update_outcome(id1, pnl=3000.0, accuracy=1)
+
+    # High-confidence loss
+    id2 = logger.log_decision(
+        stock_code="000660",
+        market="KR",
+        exchange_code="KRX",
+        action="SELL",
+        confidence=90,
+        rationale="Wrong prediction",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.update_outcome(id2, pnl=-2000.0, accuracy=0)
+
+    # Low-confidence loss (should be ignored)
+    id3 = logger.log_decision(
+        stock_code="035420",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=70,
+        rationale="Low confidence, wrong",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.update_outcome(id3, pnl=-1500.0, accuracy=0)
+
+    # Get high-confidence losing decisions
+    losers = logger.get_losing_decisions(min_confidence=80, min_loss=-1000.0)
+    assert len(losers) == 1
+    assert losers[0].decision_id == id2
+    assert losers[0].outcome_pnl == -2000.0
+    assert losers[0].confidence == 90
+
+
+def test_get_decision_by_id_not_found(logger: DecisionLogger) -> None:
+    """Test that get_decision_by_id returns None for non-existent ID."""
+    decision = logger.get_decision_by_id("non-existent-uuid")
+    assert decision is None
+
+
+def test_unreviewed_limit(logger: DecisionLogger) -> None:
+    """Test that get_unreviewed_decisions respects limit parameter."""
+    # Create 5 unreviewed decisions
+    for i in range(5):
+        logger.log_decision(
+            stock_code=f"00{i}",
+            market="KR",
+            exchange_code="KRX",
+            action="HOLD",
+            confidence=85,
+            rationale=f"Decision {i}",
+            context_snapshot={},
+            input_data={},
+        )
+
+    # Get only 3
+    unreviewed = logger.get_unreviewed_decisions(limit=3)
+    assert len(unreviewed) == 3
+
+
+def test_decision_log_dataclass() -> None:
+    """Test DecisionLog dataclass creation."""
+    now = datetime.now(UTC).isoformat()
+    log = DecisionLog(
+        decision_id="test-uuid",
+        timestamp=now,
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=85,
+        rationale="Test",
+        context_snapshot={"L1": "data"},
+        input_data={"price": 100.0},
+    )
+
+    assert log.decision_id == "test-uuid"
+    assert log.action == "BUY"
+    assert log.confidence == 85
+    assert log.reviewed is False
+    assert log.outcome_pnl is None

tests/test_evolution.py

@@ -0,0 +1,685 @@
+"""Tests for the Evolution Engine components.
+
+Tests cover:
+- EvolutionOptimizer: failure analysis and strategy generation
+- ABTester: A/B testing and statistical comparison
+- PerformanceTracker: metrics tracking and dashboard
+"""
+
+from __future__ import annotations
+
+import json
+import sqlite3
+import tempfile
+from datetime import UTC, datetime
+from pathlib import Path
+from unittest.mock import AsyncMock, Mock, patch
+
+import pytest
+
+from src.config import Settings
+from src.db import init_db, log_trade
+from src.evolution.ab_test import ABTester
+from src.evolution.optimizer import EvolutionOptimizer
+from src.evolution.performance_tracker import (
+    PerformanceDashboard,
+    PerformanceTracker,
+    StrategyMetrics,
+)
+from src.logging.decision_logger import DecisionLogger
+
+# ------------------------------------------------------------------
+# Fixtures
+# ------------------------------------------------------------------
+
+
+@pytest.fixture
+def db_conn() -> sqlite3.Connection:
+    """Provide an in-memory database with initialized schema."""
+    return init_db(":memory:")
+
+
+@pytest.fixture
+def settings() -> Settings:
+    """Provide test settings."""
+    return Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+        GEMINI_MODEL="gemini-pro",
+        DB_PATH=":memory:",
+    )
+
+
+@pytest.fixture
+def optimizer(settings: Settings) -> EvolutionOptimizer:
+    """Provide an EvolutionOptimizer instance."""
+    return EvolutionOptimizer(settings)
+
+
+@pytest.fixture
+def decision_logger(db_conn: sqlite3.Connection) -> DecisionLogger:
+    """Provide a DecisionLogger instance."""
+    return DecisionLogger(db_conn)
+
+
+@pytest.fixture
+def ab_tester() -> ABTester:
+    """Provide an ABTester instance."""
+    return ABTester(significance_level=0.05)
+
+
+@pytest.fixture
+def performance_tracker(settings: Settings) -> PerformanceTracker:
+    """Provide a PerformanceTracker instance."""
+    return PerformanceTracker(db_path=":memory:")
+
+
+# ------------------------------------------------------------------
+# EvolutionOptimizer Tests
+# ------------------------------------------------------------------
+
+
+def test_analyze_failures_uses_decision_logger(optimizer: EvolutionOptimizer) -> None:
+    """Test that analyze_failures uses DecisionLogger.get_losing_decisions()."""
+    # Add some losing decisions to the database
+    logger = optimizer._decision_logger
+
+    # High-confidence loss
+    id1 = logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=85,
+        rationale="Expected growth",
+        context_snapshot={"L1": {"price": 70000}},
+        input_data={"price": 70000, "volume": 1000},
+    )
+    logger.update_outcome(id1, pnl=-2000.0, accuracy=0)
+
+    # Another high-confidence loss
+    id2 = logger.log_decision(
+        stock_code="000660",
+        market="KR",
+        exchange_code="KRX",
+        action="SELL",
+        confidence=90,
+        rationale="Expected drop",
+        context_snapshot={"L1": {"price": 100000}},
+        input_data={"price": 100000, "volume": 500},
+    )
+    logger.update_outcome(id2, pnl=-1500.0, accuracy=0)
+
+    # Low-confidence loss (should be ignored)
+    id3 = logger.log_decision(
+        stock_code="035420",
+        market="KR",
+        exchange_code="KRX",
+        action="HOLD",
+        confidence=70,
+        rationale="Uncertain",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.update_outcome(id3, pnl=-500.0, accuracy=0)
+
+    # Analyze failures
+    failures = optimizer.analyze_failures(limit=10)
+
+    # Should get 2 failures (confidence >= 80)
+    assert len(failures) == 2
+    assert all(f["confidence"] >= 80 for f in failures)
+    assert all(f["outcome_pnl"] <= -100.0 for f in failures)
+
+
+def test_analyze_failures_empty_database(optimizer: EvolutionOptimizer) -> None:
+    """Test analyze_failures with no losing decisions."""
+    failures = optimizer.analyze_failures()
+    assert failures == []
+
+
+def test_identify_failure_patterns(optimizer: EvolutionOptimizer) -> None:
+    """Test identification of failure patterns."""
+    failures = [
+        {
+            "decision_id": "1",
+            "timestamp": "2024-01-15T09:30:00+00:00",
+            "stock_code": "005930",
+            "market": "KR",
+            "exchange_code": "KRX",
+            "action": "BUY",
+            "confidence": 85,
+            "rationale": "Test",
+            "outcome_pnl": -1000.0,
+            "outcome_accuracy": 0,
+            "context_snapshot": {},
+            "input_data": {},
+        },
+        {
+            "decision_id": "2",
+            "timestamp": "2024-01-15T14:30:00+00:00",
+            "stock_code": "000660",
+            "market": "KR",
+            "exchange_code": "KRX",
+            "action": "SELL",
+            "confidence": 90,
+            "rationale": "Test",
+            "outcome_pnl": -2000.0,
+            "outcome_accuracy": 0,
+            "context_snapshot": {},
+            "input_data": {},
+        },
+        {
+            "decision_id": "3",
+            "timestamp": "2024-01-15T09:45:00+00:00",
+            "stock_code": "035420",
+            "market": "US_NASDAQ",
+            "exchange_code": "NASDAQ",
+            "action": "BUY",
+            "confidence": 80,
+            "rationale": "Test",
+            "outcome_pnl": -500.0,
+            "outcome_accuracy": 0,
+            "context_snapshot": {},
+            "input_data": {},
+        },
+    ]
+
+    patterns = optimizer.identify_failure_patterns(failures)
+
+    assert patterns["total_failures"] == 3
+    assert patterns["markets"]["KR"] == 2
+    assert patterns["markets"]["US_NASDAQ"] == 1
+    assert patterns["actions"]["BUY"] == 2
+    assert patterns["actions"]["SELL"] == 1
+    assert 9 in patterns["hours"]  # 09:30 and 09:45
+    assert 14 in patterns["hours"]  # 14:30
+    assert patterns["avg_confidence"] == 85.0
+    assert patterns["avg_loss"] == -1166.67
+
+
+def test_identify_failure_patterns_empty(optimizer: EvolutionOptimizer) -> None:
+    """Test pattern identification with no failures."""
+    patterns = optimizer.identify_failure_patterns([])
+    assert patterns["pattern_count"] == 0
+    assert patterns["patterns"] == {}
+
+
+@pytest.mark.asyncio
+async def test_generate_strategy_creates_file(optimizer: EvolutionOptimizer, tmp_path: Path) -> None:
+    """Test that generate_strategy creates a strategy file."""
+    failures = [
+        {
+            "decision_id": "1",
+            "timestamp": "2024-01-15T09:30:00+00:00",
+            "stock_code": "005930",
+            "market": "KR",
+            "action": "BUY",
+            "confidence": 85,
+            "outcome_pnl": -1000.0,
+            "context_snapshot": {},
+            "input_data": {},
+        }
+    ]
+
+    # Mock Gemini response
+    mock_response = Mock()
+    mock_response.text = """
+    # Simple strategy
+    price = market_data.get("current_price", 0)
+    if price > 50000:
+        return {"action": "BUY", "confidence": 70, "rationale": "Price above threshold"}
+    return {"action": "HOLD", "confidence": 50, "rationale": "Waiting"}
+    """
+
+    with patch.object(optimizer._client.aio.models, "generate_content", new=AsyncMock(return_value=mock_response)):
+        with patch("src.evolution.optimizer.STRATEGIES_DIR", tmp_path):
+            strategy_path = await optimizer.generate_strategy(failures)
+
+    assert strategy_path is not None
+    assert strategy_path.exists()
+    assert strategy_path.suffix == ".py"
+    assert "class Strategy_" in strategy_path.read_text()
+    assert "def evaluate" in strategy_path.read_text()
+
+
+@pytest.mark.asyncio
+async def test_generate_strategy_handles_api_error(optimizer: EvolutionOptimizer) -> None:
+    """Test that generate_strategy handles Gemini API errors gracefully."""
+    failures = [{"decision_id": "1", "timestamp": "2024-01-15T09:30:00+00:00"}]
+
+    with patch.object(
+        optimizer._client.aio.models,
+        "generate_content",
+        side_effect=Exception("API Error"),
+    ):
+        strategy_path = await optimizer.generate_strategy(failures)
+
+    assert strategy_path is None
+
+
+def test_get_performance_summary() -> None:
+    """Test getting performance summary from trades table."""
+    # Create a temporary database with trades
+    import tempfile
+    with tempfile.NamedTemporaryFile(suffix=".db", delete=False) as tmp:
+        tmp_path = tmp.name
+
+    conn = init_db(tmp_path)
+    log_trade(conn, "005930", "BUY", 85, "Test win", quantity=10, price=70000, pnl=1000.0)
+    log_trade(conn, "000660", "SELL", 90, "Test loss", quantity=5, price=100000, pnl=-500.0)
+    log_trade(conn, "035420", "BUY", 80, "Test win", quantity=8, price=50000, pnl=800.0)
+    conn.close()
+
+    # Create settings with temp database path
+    settings = Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+        GEMINI_MODEL="gemini-pro",
+        DB_PATH=tmp_path,
+    )
+
+    optimizer = EvolutionOptimizer(settings)
+    summary = optimizer.get_performance_summary()
+
+    assert summary["total_trades"] == 3
+    assert summary["wins"] == 2
+    assert summary["losses"] == 1
+    assert summary["total_pnl"] == 1300.0
+    assert summary["avg_pnl"] == 433.33
+
+    # Clean up
+    Path(tmp_path).unlink()
+
+
+def test_validate_strategy_success(optimizer: EvolutionOptimizer, tmp_path: Path) -> None:
+    """Test strategy validation when tests pass."""
+    strategy_file = tmp_path / "test_strategy.py"
+    strategy_file.write_text("# Valid strategy file")
+
+    with patch("subprocess.run") as mock_run:
+        mock_run.return_value = Mock(returncode=0, stdout="", stderr="")
+        result = optimizer.validate_strategy(strategy_file)
+
+    assert result is True
+    assert strategy_file.exists()
+
+
+def test_validate_strategy_failure(optimizer: EvolutionOptimizer, tmp_path: Path) -> None:
+    """Test strategy validation when tests fail."""
+    strategy_file = tmp_path / "test_strategy.py"
+    strategy_file.write_text("# Invalid strategy file")
+
+    with patch("subprocess.run") as mock_run:
+        mock_run.return_value = Mock(returncode=1, stdout="FAILED", stderr="")
+        result = optimizer.validate_strategy(strategy_file)
+
+    assert result is False
+    # File should be deleted on failure
+    assert not strategy_file.exists()
+
+
+# ------------------------------------------------------------------
+# ABTester Tests
+# ------------------------------------------------------------------
+
+
+def test_calculate_performance_basic(ab_tester: ABTester) -> None:
+    """Test basic performance calculation."""
+    trades = [
+        {"pnl": 1000.0},
+        {"pnl": -500.0},
+        {"pnl": 800.0},
+        {"pnl": 200.0},
+    ]
+
+    perf = ab_tester.calculate_performance(trades, "TestStrategy")
+
+    assert perf.strategy_name == "TestStrategy"
+    assert perf.total_trades == 4
+    assert perf.wins == 3
+    assert perf.losses == 1
+    assert perf.total_pnl == 1500.0
+    assert perf.avg_pnl == 375.0
+    assert perf.win_rate == 75.0
+    assert perf.sharpe_ratio is not None
+
+
+def test_calculate_performance_empty(ab_tester: ABTester) -> None:
+    """Test performance calculation with no trades."""
+    perf = ab_tester.calculate_performance([], "EmptyStrategy")
+
+    assert perf.total_trades == 0
+    assert perf.wins == 0
+    assert perf.losses == 0
+    assert perf.total_pnl == 0.0
+    assert perf.avg_pnl == 0.0
+    assert perf.win_rate == 0.0
+    assert perf.sharpe_ratio is None
+
+
+def test_compare_strategies_significant_difference(ab_tester: ABTester) -> None:
+    """Test strategy comparison with significant performance difference."""
+    # Strategy A: consistently profitable
+    trades_a = [{"pnl": 1000.0} for _ in range(30)]
+
+    # Strategy B: consistently losing
+    trades_b = [{"pnl": -500.0} for _ in range(30)]
+
+    result = ab_tester.compare_strategies(trades_a, trades_b, "Strategy A", "Strategy B")
+
+    # scipy returns np.True_ instead of Python bool
+    assert bool(result.is_significant) is True
+    assert result.winner == "Strategy A"
+    assert result.p_value < 0.05
+    assert result.performance_a.avg_pnl > result.performance_b.avg_pnl
+
+
+def test_compare_strategies_no_difference(ab_tester: ABTester) -> None:
+    """Test strategy comparison with no significant difference."""
+    # Both strategies have similar performance
+    trades_a = [{"pnl": 100.0}, {"pnl": -50.0}, {"pnl": 80.0}]
+    trades_b = [{"pnl": 90.0}, {"pnl": -60.0}, {"pnl": 85.0}]
+
+    result = ab_tester.compare_strategies(trades_a, trades_b, "Strategy A", "Strategy B")
+
+    # With small samples and similar performance, likely not significant
+    assert result.winner is None or not result.is_significant
+
+
+def test_should_deploy_meets_criteria(ab_tester: ABTester) -> None:
+    """Test deployment decision when criteria are met."""
+    # Create a winning result that meets criteria
+    trades_a = [{"pnl": 1000.0} for _ in range(25)]  # 100% win rate
+    trades_b = [{"pnl": -500.0} for _ in range(25)]
+
+    result = ab_tester.compare_strategies(trades_a, trades_b, "Winner", "Loser")
+
+    should_deploy = ab_tester.should_deploy(result, min_win_rate=60.0, min_trades=20)
+
+    assert should_deploy is True
+
+
+def test_should_deploy_insufficient_trades(ab_tester: ABTester) -> None:
+    """Test deployment decision with insufficient trades."""
+    trades_a = [{"pnl": 1000.0} for _ in range(10)]  # Only 10 trades
+    trades_b = [{"pnl": -500.0} for _ in range(10)]
+
+    result = ab_tester.compare_strategies(trades_a, trades_b, "Winner", "Loser")
+
+    should_deploy = ab_tester.should_deploy(result, min_win_rate=60.0, min_trades=20)
+
+    assert should_deploy is False
+
+
+def test_should_deploy_low_win_rate(ab_tester: ABTester) -> None:
+    """Test deployment decision with low win rate."""
+    # Mix of wins and losses, below 60% win rate
+    trades_a = [{"pnl": 100.0}] * 10 + [{"pnl": -100.0}] * 15  # 40% win rate
+    trades_b = [{"pnl": -500.0} for _ in range(25)]
+
+    result = ab_tester.compare_strategies(trades_a, trades_b, "LowWinner", "Loser")
+
+    should_deploy = ab_tester.should_deploy(result, min_win_rate=60.0, min_trades=20)
+
+    assert should_deploy is False
+
+
+def test_should_deploy_not_significant(ab_tester: ABTester) -> None:
+    """Test deployment decision when difference is not significant."""
+    # Use more varied data to ensure statistical insignificance
+    trades_a = [{"pnl": 100.0}, {"pnl": -50.0}] * 12 + [{"pnl": 100.0}]
+    trades_b = [{"pnl": 95.0}, {"pnl": -45.0}] * 12 + [{"pnl": 95.0}]
+
+    result = ab_tester.compare_strategies(trades_a, trades_b, "A", "B")
+
+    should_deploy = ab_tester.should_deploy(result, min_win_rate=60.0, min_trades=20)
+
+    # Not significant or not profitable enough
+    # Even if significant, win rate is 50% which is below 60% threshold
+    assert should_deploy is False
+
+
+# ------------------------------------------------------------------
+# PerformanceTracker Tests
+# ------------------------------------------------------------------
+
+
+def test_get_strategy_metrics(db_conn: sqlite3.Connection) -> None:
+    """Test getting strategy metrics."""
+    # Add some trades
+    log_trade(db_conn, "005930", "BUY", 85, "Win 1", quantity=10, price=70000, pnl=1000.0)
+    log_trade(db_conn, "000660", "SELL", 90, "Loss 1", quantity=5, price=100000, pnl=-500.0)
+    log_trade(db_conn, "035420", "BUY", 80, "Win 2", quantity=8, price=50000, pnl=800.0)
+    log_trade(db_conn, "005930", "HOLD", 75, "Hold", quantity=0, price=70000, pnl=0.0)
+
+    tracker = PerformanceTracker(db_path=":memory:")
+    # Manually set connection for testing
+    tracker._db_path = db_conn
+
+    # Need to use the same connection
+    with patch("sqlite3.connect", return_value=db_conn):
+        metrics = tracker.get_strategy_metrics()
+
+    assert metrics.total_trades == 4
+    assert metrics.wins == 2
+    assert metrics.losses == 1
+    assert metrics.holds == 1
+    assert metrics.win_rate == 50.0
+    assert metrics.total_pnl == 1300.0
+
+
+def test_calculate_improvement_trend_improving(performance_tracker: PerformanceTracker) -> None:
+    """Test improvement trend calculation for improving strategy."""
+    metrics = [
+        StrategyMetrics(
+            strategy_name="test",
+            period_start="2024-01-01",
+            period_end="2024-01-07",
+            total_trades=10,
+            wins=5,
+            losses=5,
+            holds=0,
+            win_rate=50.0,
+            avg_pnl=100.0,
+            total_pnl=1000.0,
+            best_trade=500.0,
+            worst_trade=-300.0,
+            avg_confidence=75.0,
+        ),
+        StrategyMetrics(
+            strategy_name="test",
+            period_start="2024-01-08",
+            period_end="2024-01-14",
+            total_trades=10,
+            wins=7,
+            losses=3,
+            holds=0,
+            win_rate=70.0,
+            avg_pnl=200.0,
+            total_pnl=2000.0,
+            best_trade=600.0,
+            worst_trade=-200.0,
+            avg_confidence=80.0,
+        ),
+    ]
+
+    trend = performance_tracker.calculate_improvement_trend(metrics)
+
+    assert trend["trend"] == "improving"
+    assert trend["win_rate_change"] == 20.0
+    assert trend["pnl_change"] == 100.0
+    assert trend["confidence_change"] == 5.0
+
+
+def test_calculate_improvement_trend_declining(performance_tracker: PerformanceTracker) -> None:
+    """Test improvement trend calculation for declining strategy."""
+    metrics = [
+        StrategyMetrics(
+            strategy_name="test",
+            period_start="2024-01-01",
+            period_end="2024-01-07",
+            total_trades=10,
+            wins=7,
+            losses=3,
+            holds=0,
+            win_rate=70.0,
+            avg_pnl=200.0,
+            total_pnl=2000.0,
+            best_trade=600.0,
+            worst_trade=-200.0,
+            avg_confidence=80.0,
+        ),
+        StrategyMetrics(
+            strategy_name="test",
+            period_start="2024-01-08",
+            period_end="2024-01-14",
+            total_trades=10,
+            wins=4,
+            losses=6,
+            holds=0,
+            win_rate=40.0,
+            avg_pnl=-50.0,
+            total_pnl=-500.0,
+            best_trade=300.0,
+            worst_trade=-400.0,
+            avg_confidence=70.0,
+        ),
+    ]
+
+    trend = performance_tracker.calculate_improvement_trend(metrics)
+
+    assert trend["trend"] == "declining"
+    assert trend["win_rate_change"] == -30.0
+    assert trend["pnl_change"] == -250.0
+
+
+def test_calculate_improvement_trend_insufficient_data(performance_tracker: PerformanceTracker) -> None:
+    """Test improvement trend with insufficient data."""
+    metrics = [
+        StrategyMetrics(
+            strategy_name="test",
+            period_start="2024-01-01",
+            period_end="2024-01-07",
+            total_trades=10,
+            wins=5,
+            losses=5,
+            holds=0,
+            win_rate=50.0,
+            avg_pnl=100.0,
+            total_pnl=1000.0,
+            best_trade=500.0,
+            worst_trade=-300.0,
+            avg_confidence=75.0,
+        )
+    ]
+
+    trend = performance_tracker.calculate_improvement_trend(metrics)
+
+    assert trend["trend"] == "insufficient_data"
+    assert trend["win_rate_change"] == 0.0
+    assert trend["pnl_change"] == 0.0
+
+
+def test_export_dashboard_json(performance_tracker: PerformanceTracker) -> None:
+    """Test exporting dashboard as JSON."""
+    overall_metrics = StrategyMetrics(
+        strategy_name="test",
+        period_start="2024-01-01",
+        period_end="2024-01-31",
+        total_trades=100,
+        wins=60,
+        losses=40,
+        holds=10,
+        win_rate=60.0,
+        avg_pnl=150.0,
+        total_pnl=15000.0,
+        best_trade=1000.0,
+        worst_trade=-500.0,
+        avg_confidence=80.0,
+    )
+
+    dashboard = PerformanceDashboard(
+        generated_at=datetime.now(UTC).isoformat(),
+        overall_metrics=overall_metrics,
+        daily_metrics=[],
+        weekly_metrics=[],
+        improvement_trend={"trend": "improving", "win_rate_change": 10.0},
+    )
+
+    json_output = performance_tracker.export_dashboard_json(dashboard)
+
+    # Verify it's valid JSON
+    data = json.loads(json_output)
+    assert "generated_at" in data
+    assert "overall_metrics" in data
+    assert data["overall_metrics"]["total_trades"] == 100
+    assert data["overall_metrics"]["win_rate"] == 60.0
+
+
+def test_generate_dashboard() -> None:
+    """Test generating a complete dashboard."""
+    # Create tracker with temp database
+    with tempfile.NamedTemporaryFile(suffix=".db", delete=False) as tmp:
+        tmp_path = tmp.name
+
+    # Initialize with data
+    conn = init_db(tmp_path)
+    log_trade(conn, "005930", "BUY", 85, "Win", quantity=10, price=70000, pnl=1000.0)
+    log_trade(conn, "000660", "SELL", 90, "Loss", quantity=5, price=100000, pnl=-500.0)
+    conn.close()
+
+    tracker = PerformanceTracker(db_path=tmp_path)
+    dashboard = tracker.generate_dashboard()
+
+    assert isinstance(dashboard, PerformanceDashboard)
+    assert dashboard.overall_metrics.total_trades == 2
+    assert len(dashboard.daily_metrics) == 7
+    assert len(dashboard.weekly_metrics) == 4
+    assert "trend" in dashboard.improvement_trend
+
+    # Clean up
+    Path(tmp_path).unlink()
+
+
+# ------------------------------------------------------------------
+# Integration Tests
+# ------------------------------------------------------------------
+
+
+@pytest.mark.asyncio
+async def test_full_evolution_pipeline(optimizer: EvolutionOptimizer, tmp_path: Path) -> None:
+    """Test the complete evolution pipeline."""
+    # Add losing decisions
+    logger = optimizer._decision_logger
+    id1 = logger.log_decision(
+        stock_code="005930",
+        market="KR",
+        exchange_code="KRX",
+        action="BUY",
+        confidence=85,
+        rationale="Expected growth",
+        context_snapshot={},
+        input_data={},
+    )
+    logger.update_outcome(id1, pnl=-2000.0, accuracy=0)
+
+    # Mock Gemini and subprocess
+    mock_response = Mock()
+    mock_response.text = 'return {"action": "HOLD", "confidence": 50, "rationale": "Test"}'
+
+    with patch.object(optimizer._client.aio.models, "generate_content", new=AsyncMock(return_value=mock_response)):
+        with patch("src.evolution.optimizer.STRATEGIES_DIR", tmp_path):
+            with patch("subprocess.run") as mock_run:
+                mock_run.return_value = Mock(returncode=0, stdout="", stderr="")
+
+                result = await optimizer.evolve()
+
+    assert result is not None
+    assert "title" in result
+    assert "branch" in result
+    assert "status" in result

tests/test_latency_control.py

@@ -0,0 +1,558 @@
+"""Tests for latency control system (criticality assessment and priority queue)."""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+from src.core.criticality import CriticalityAssessor, CriticalityLevel
+from src.core.priority_queue import PriorityTask, PriorityTaskQueue
+
+# ---------------------------------------------------------------------------
+# CriticalityAssessor Tests
+# ---------------------------------------------------------------------------
+
+
+class TestCriticalityAssessor:
+    """Test suite for criticality assessment logic."""
+
+    def test_market_closed_returns_low(self) -> None:
+        """Market closed should return LOW priority."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=50.0,
+            volume_surge=1.0,
+            is_market_open=False,
+        )
+        assert level == CriticalityLevel.LOW
+
+    def test_very_low_volatility_returns_low(self) -> None:
+        """Very low volatility should return LOW priority."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=20.0,  # Below 30.0 threshold
+            volume_surge=1.0,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.LOW
+
+    def test_critical_pnl_threshold_triggered(self) -> None:
+        """P&L below -2.5% should trigger CRITICAL."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=-2.6,  # Below -2.5% threshold
+            volatility_score=50.0,
+            volume_surge=1.0,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+    def test_critical_pnl_at_circuit_breaker_proximity(self) -> None:
+        """P&L at exactly -2.5% (near -3.0% breaker) should be CRITICAL."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=-2.5,
+            volatility_score=50.0,
+            volume_surge=1.0,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+    def test_critical_price_change_positive(self) -> None:
+        """Large positive price change (>5%) should trigger CRITICAL."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=50.0,
+            volume_surge=1.0,
+            price_change_1m=5.5,  # Above 5.0% threshold
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+    def test_critical_price_change_negative(self) -> None:
+        """Large negative price change (<-5%) should trigger CRITICAL."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=50.0,
+            volume_surge=1.0,
+            price_change_1m=-6.0,  # Below -5.0% threshold
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+    def test_critical_volume_surge(self) -> None:
+        """Extreme volume surge (>10x) should trigger CRITICAL."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=50.0,
+            volume_surge=12.0,  # Above 10.0x threshold
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+    def test_high_volatility_returns_high(self) -> None:
+        """High volatility score should return HIGH priority."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=75.0,  # Above 70.0 threshold
+            volume_surge=1.0,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.HIGH
+
+    def test_normal_conditions_return_normal(self) -> None:
+        """Normal market conditions should return NORMAL priority."""
+        assessor = CriticalityAssessor()
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.5,
+            volatility_score=50.0,  # Between 30-70
+            volume_surge=1.5,
+            price_change_1m=1.0,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.NORMAL
+
+    def test_custom_thresholds(self) -> None:
+        """Custom thresholds should be respected."""
+        assessor = CriticalityAssessor(
+            critical_pnl_threshold=-1.0,
+            critical_price_change_threshold=3.0,
+            critical_volume_surge_threshold=5.0,
+            high_volatility_threshold=60.0,
+            low_volatility_threshold=20.0,
+        )
+
+        # Test custom P&L threshold
+        level = assessor.assess_market_conditions(
+            pnl_pct=-1.1,
+            volatility_score=50.0,
+            volume_surge=1.0,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+        # Test custom price change threshold
+        level = assessor.assess_market_conditions(
+            pnl_pct=0.0,
+            volatility_score=50.0,
+            volume_surge=1.0,
+            price_change_1m=3.5,
+            is_market_open=True,
+        )
+        assert level == CriticalityLevel.CRITICAL
+
+    def test_get_timeout_returns_correct_values(self) -> None:
+        """Timeout values should match specification."""
+        assessor = CriticalityAssessor()
+
+        assert assessor.get_timeout(CriticalityLevel.CRITICAL) == 5.0
+        assert assessor.get_timeout(CriticalityLevel.HIGH) == 30.0
+        assert assessor.get_timeout(CriticalityLevel.NORMAL) == 60.0
+        assert assessor.get_timeout(CriticalityLevel.LOW) is None
+
+
+# ---------------------------------------------------------------------------
+# PriorityTaskQueue Tests
+# ---------------------------------------------------------------------------
+
+
+class TestPriorityTaskQueue:
+    """Test suite for priority queue implementation."""
+
+    @pytest.mark.asyncio
+    async def test_enqueue_task(self) -> None:
+        """Tasks should be enqueued successfully."""
+        queue = PriorityTaskQueue()
+
+        success = await queue.enqueue(
+            task_id="test-1",
+            criticality=CriticalityLevel.NORMAL,
+            task_data={"action": "test"},
+        )
+
+        assert success is True
+        assert await queue.size() == 1
+
+    @pytest.mark.asyncio
+    async def test_enqueue_rejects_when_full(self) -> None:
+        """Queue should reject tasks when full."""
+        queue = PriorityTaskQueue(max_size=2)
+
+        # Fill the queue
+        await queue.enqueue("task-1", CriticalityLevel.NORMAL, {})
+        await queue.enqueue("task-2", CriticalityLevel.NORMAL, {})
+
+        # Third task should be rejected
+        success = await queue.enqueue("task-3", CriticalityLevel.NORMAL, {})
+        assert success is False
+        assert await queue.size() == 2
+
+    @pytest.mark.asyncio
+    async def test_dequeue_returns_highest_priority(self) -> None:
+        """Dequeue should return highest priority task first."""
+        queue = PriorityTaskQueue()
+
+        # Enqueue tasks in reverse priority order
+        await queue.enqueue("low", CriticalityLevel.LOW, {"priority": 3})
+        await queue.enqueue("normal", CriticalityLevel.NORMAL, {"priority": 2})
+        await queue.enqueue("high", CriticalityLevel.HIGH, {"priority": 1})
+        await queue.enqueue("critical", CriticalityLevel.CRITICAL, {"priority": 0})
+
+        # Dequeue should return CRITICAL first
+        task = await queue.dequeue(timeout=1.0)
+        assert task is not None
+        assert task.task_id == "critical"
+        assert task.priority == 0
+
+        # Then HIGH
+        task = await queue.dequeue(timeout=1.0)
+        assert task is not None
+        assert task.task_id == "high"
+        assert task.priority == 1
+
+    @pytest.mark.asyncio
+    async def test_dequeue_fifo_within_same_priority(self) -> None:
+        """Tasks with same priority should be FIFO."""
+        queue = PriorityTaskQueue()
+
+        # Enqueue multiple tasks with same priority
+        await queue.enqueue("task-1", CriticalityLevel.NORMAL, {})
+        await asyncio.sleep(0.01)  # Small delay to ensure different timestamps
+        await queue.enqueue("task-2", CriticalityLevel.NORMAL, {})
+        await asyncio.sleep(0.01)
+        await queue.enqueue("task-3", CriticalityLevel.NORMAL, {})
+
+        # Should dequeue in FIFO order
+        task1 = await queue.dequeue(timeout=1.0)
+        task2 = await queue.dequeue(timeout=1.0)
+        task3 = await queue.dequeue(timeout=1.0)
+
+        assert task1 is not None and task1.task_id == "task-1"
+        assert task2 is not None and task2.task_id == "task-2"
+        assert task3 is not None and task3.task_id == "task-3"
+
+    @pytest.mark.asyncio
+    async def test_dequeue_returns_none_when_empty(self) -> None:
+        """Dequeue should return None when queue is empty after timeout."""
+        queue = PriorityTaskQueue()
+
+        task = await queue.dequeue(timeout=0.1)
+        assert task is None
+
+    @pytest.mark.asyncio
+    async def test_execute_with_timeout_success(self) -> None:
+        """Task execution should succeed within timeout."""
+        queue = PriorityTaskQueue()
+
+        # Create a simple async callback
+        async def test_callback() -> str:
+            await asyncio.sleep(0.01)
+            return "success"
+
+        task = PriorityTask(
+            priority=0,
+            timestamp=0.0,
+            task_id="test",
+            task_data={},
+            callback=test_callback,
+        )
+
+        result = await queue.execute_with_timeout(task, timeout=1.0)
+        assert result == "success"
+
+    @pytest.mark.asyncio
+    async def test_execute_with_timeout_raises_timeout_error(self) -> None:
+        """Task execution should raise TimeoutError if exceeds timeout."""
+        queue = PriorityTaskQueue()
+
+        # Create a slow async callback
+        async def slow_callback() -> str:
+            await asyncio.sleep(1.0)
+            return "too slow"
+
+        task = PriorityTask(
+            priority=0,
+            timestamp=0.0,
+            task_id="test",
+            task_data={},
+            callback=slow_callback,
+        )
+
+        with pytest.raises(asyncio.TimeoutError):
+            await queue.execute_with_timeout(task, timeout=0.1)
+
+    @pytest.mark.asyncio
+    async def test_execute_with_timeout_propagates_exceptions(self) -> None:
+        """Task execution should propagate exceptions from callback."""
+        queue = PriorityTaskQueue()
+
+        # Create a failing async callback
+        async def failing_callback() -> None:
+            raise ValueError("Test error")
+
+        task = PriorityTask(
+            priority=0,
+            timestamp=0.0,
+            task_id="test",
+            task_data={},
+            callback=failing_callback,
+        )
+
+        with pytest.raises(ValueError, match="Test error"):
+            await queue.execute_with_timeout(task, timeout=1.0)
+
+    @pytest.mark.asyncio
+    async def test_execute_without_timeout(self) -> None:
+        """Task execution should work without timeout (LOW priority)."""
+        queue = PriorityTaskQueue()
+
+        async def test_callback() -> str:
+            await asyncio.sleep(0.01)
+            return "success"
+
+        task = PriorityTask(
+            priority=3,
+            timestamp=0.0,
+            task_id="test",
+            task_data={},
+            callback=test_callback,
+        )
+
+        result = await queue.execute_with_timeout(task, timeout=None)
+        assert result == "success"
+
+    @pytest.mark.asyncio
+    async def test_get_metrics(self) -> None:
+        """Queue should track metrics correctly."""
+        queue = PriorityTaskQueue()
+
+        # Enqueue and dequeue some tasks
+        await queue.enqueue("task-1", CriticalityLevel.CRITICAL, {})
+        await queue.enqueue("task-2", CriticalityLevel.HIGH, {})
+        await queue.enqueue("task-3", CriticalityLevel.NORMAL, {})
+
+        await queue.dequeue(timeout=1.0)
+        await queue.dequeue(timeout=1.0)
+
+        metrics = await queue.get_metrics()
+
+        assert metrics.total_enqueued == 3
+        assert metrics.total_dequeued == 2
+        assert metrics.current_size == 1
+
+    @pytest.mark.asyncio
+    async def test_wait_time_metrics(self) -> None:
+        """Queue should track wait times per criticality level."""
+        queue = PriorityTaskQueue()
+
+        # Enqueue tasks with different criticality
+        await queue.enqueue("critical-1", CriticalityLevel.CRITICAL, {})
+        await asyncio.sleep(0.05)  # Add some wait time
+
+        await queue.dequeue(timeout=1.0)
+
+        metrics = await queue.get_metrics()
+
+        # Should have wait time metrics for CRITICAL
+        assert CriticalityLevel.CRITICAL in metrics.avg_wait_time
+        assert metrics.avg_wait_time[CriticalityLevel.CRITICAL] > 0.0
+
+    @pytest.mark.asyncio
+    async def test_clear_queue(self) -> None:
+        """Clear should remove all tasks from queue."""
+        queue = PriorityTaskQueue()
+
+        await queue.enqueue("task-1", CriticalityLevel.NORMAL, {})
+        await queue.enqueue("task-2", CriticalityLevel.NORMAL, {})
+        await queue.enqueue("task-3", CriticalityLevel.NORMAL, {})
+
+        cleared = await queue.clear()
+
+        assert cleared == 3
+        assert await queue.size() == 0
+
+    @pytest.mark.asyncio
+    async def test_concurrent_enqueue_dequeue(self) -> None:
+        """Queue should handle concurrent operations safely."""
+        queue = PriorityTaskQueue()
+
+        # Concurrent enqueue operations
+        async def enqueue_tasks() -> None:
+            for i in range(10):
+                await queue.enqueue(
+                    f"task-{i}",
+                    CriticalityLevel.NORMAL,
+                    {"index": i},
+                )
+
+        # Concurrent dequeue operations
+        async def dequeue_tasks() -> list[str]:
+            tasks = []
+            for _ in range(10):
+                task = await queue.dequeue(timeout=1.0)
+                if task:
+                    tasks.append(task.task_id)
+                await asyncio.sleep(0.01)
+            return tasks
+
+        # Run both concurrently
+        enqueue_task = asyncio.create_task(enqueue_tasks())
+        dequeue_task = asyncio.create_task(dequeue_tasks())
+
+        await enqueue_task
+        dequeued_ids = await dequeue_task
+
+        # All tasks should be processed
+        assert len(dequeued_ids) == 10
+
+    @pytest.mark.asyncio
+    async def test_timeout_metric_tracking(self) -> None:
+        """Queue should track timeout occurrences."""
+        queue = PriorityTaskQueue()
+
+        async def slow_callback() -> str:
+            await asyncio.sleep(1.0)
+            return "too slow"
+
+        task = PriorityTask(
+            priority=0,
+            timestamp=0.0,
+            task_id="test",
+            task_data={},
+            callback=slow_callback,
+        )
+
+        try:
+            await queue.execute_with_timeout(task, timeout=0.1)
+        except TimeoutError:
+            pass
+
+        metrics = await queue.get_metrics()
+        assert metrics.total_timeouts == 1
+
+    @pytest.mark.asyncio
+    async def test_error_metric_tracking(self) -> None:
+        """Queue should track execution errors."""
+        queue = PriorityTaskQueue()
+
+        async def failing_callback() -> None:
+            raise ValueError("Test error")
+
+        task = PriorityTask(
+            priority=0,
+            timestamp=0.0,
+            task_id="test",
+            task_data={},
+            callback=failing_callback,
+        )
+
+        try:
+            await queue.execute_with_timeout(task, timeout=1.0)
+        except ValueError:
+            pass
+
+        metrics = await queue.get_metrics()
+        assert metrics.total_errors == 1
+
+
+# ---------------------------------------------------------------------------
+# Integration Tests
+# ---------------------------------------------------------------------------
+
+
+class TestLatencyControlIntegration:
+    """Integration tests for criticality assessment and priority queue."""
+
+    @pytest.mark.asyncio
+    async def test_critical_task_bypass_queue(self) -> None:
+        """CRITICAL tasks should bypass lower priority tasks."""
+        queue = PriorityTaskQueue()
+
+        # Add normal priority tasks
+        await queue.enqueue("normal-1", CriticalityLevel.NORMAL, {})
+        await queue.enqueue("normal-2", CriticalityLevel.NORMAL, {})
+
+        # Add critical task (should jump to front)
+        await queue.enqueue("critical", CriticalityLevel.CRITICAL, {})
+
+        # Dequeue should return critical first
+        task = await queue.dequeue(timeout=1.0)
+        assert task is not None
+        assert task.task_id == "critical"
+
+    @pytest.mark.asyncio
+    async def test_timeout_enforcement_by_criticality(self) -> None:
+        """Timeout enforcement should match criticality level."""
+        assessor = CriticalityAssessor()
+
+        # CRITICAL should have 5s timeout
+        critical_timeout = assessor.get_timeout(CriticalityLevel.CRITICAL)
+        assert critical_timeout == 5.0
+
+        # HIGH should have 30s timeout
+        high_timeout = assessor.get_timeout(CriticalityLevel.HIGH)
+        assert high_timeout == 30.0
+
+        # NORMAL should have 60s timeout
+        normal_timeout = assessor.get_timeout(CriticalityLevel.NORMAL)
+        assert normal_timeout == 60.0
+
+        # LOW should have no timeout
+        low_timeout = assessor.get_timeout(CriticalityLevel.LOW)
+        assert low_timeout is None
+
+    @pytest.mark.asyncio
+    async def test_fast_path_execution_for_critical(self) -> None:
+        """CRITICAL tasks should complete quickly."""
+        queue = PriorityTaskQueue()
+
+        # Create a fast callback simulating fast-path execution
+        async def fast_path_callback() -> str:
+            # Simulate simplified decision flow
+            await asyncio.sleep(0.01)  # Very fast execution
+            return "fast_path_complete"
+
+        task = PriorityTask(
+            priority=0,  # CRITICAL
+            timestamp=0.0,
+            task_id="critical-fast",
+            task_data={},
+            callback=fast_path_callback,
+        )
+
+        import time
+
+        start = time.time()
+        result = await queue.execute_with_timeout(task, timeout=5.0)
+        elapsed = time.time() - start
+
+        assert result == "fast_path_complete"
+        assert elapsed < 5.0  # Should complete well under CRITICAL timeout
+
+    @pytest.mark.asyncio
+    async def test_graceful_degradation_when_queue_full(self) -> None:
+        """System should gracefully handle full queue."""
+        queue = PriorityTaskQueue(max_size=2)
+
+        # Fill the queue
+        await queue.enqueue("task-1", CriticalityLevel.NORMAL, {})
+        await queue.enqueue("task-2", CriticalityLevel.NORMAL, {})
+
+        # Try to add more tasks
+        success = await queue.enqueue("task-3", CriticalityLevel.NORMAL, {})
+        assert success is False
+
+        # Queue should still function
+        task = await queue.dequeue(timeout=1.0)
+        assert task is not None
+
+        # Now we can add another task
+        success = await queue.enqueue("task-4", CriticalityLevel.NORMAL, {})
+        assert success is True

tests/test_token_efficiency.py

@@ -0,0 +1,663 @@
+"""Tests for token efficiency optimization components.
+
+Tests cover:
+- Prompt compression and optimization
+- Context selection logic
+- Summarization
+- Caching
+- Token reduction metrics
+"""
+
+from __future__ import annotations
+
+import sqlite3
+import time
+
+import pytest
+
+from src.brain.cache import DecisionCache
+from src.brain.context_selector import ContextSelector, DecisionType
+from src.brain.gemini_client import TradeDecision
+from src.brain.prompt_optimizer import PromptOptimizer, TokenMetrics
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+from src.context.summarizer import ContextSummarizer, SummaryStats
+
+# ============================================================================
+# Prompt Optimizer Tests
+# ============================================================================
+
+
+class TestPromptOptimizer:
+    """Tests for PromptOptimizer."""
+
+    def test_estimate_tokens(self):
+        """Test token estimation."""
+        optimizer = PromptOptimizer()
+
+        # Empty text
+        assert optimizer.estimate_tokens("") == 0
+
+        # Short text (4 chars = 1 token estimate)
+        assert optimizer.estimate_tokens("test") == 1
+
+        # Longer text
+        text = "This is a longer piece of text for testing token estimation."
+        tokens = optimizer.estimate_tokens(text)
+        assert tokens > 0
+        assert tokens == len(text) // 4
+
+    def test_count_tokens(self):
+        """Test token counting metrics."""
+        optimizer = PromptOptimizer()
+
+        text = "Hello world, this is a test."
+        metrics = optimizer.count_tokens(text)
+
+        assert isinstance(metrics, TokenMetrics)
+        assert metrics.char_count == len(text)
+        assert metrics.word_count == 6
+        assert metrics.estimated_tokens > 0
+
+    def test_compress_json(self):
+        """Test JSON compression."""
+        optimizer = PromptOptimizer()
+
+        data = {
+            "action": "BUY",
+            "confidence": 85,
+            "rationale": "Strong uptrend",
+        }
+
+        compressed = optimizer.compress_json(data)
+
+        # Should have no newlines and minimal whitespace
+        assert "\n" not in compressed
+        # Note: JSON values may contain spaces (e.g., "Strong uptrend")
+        # but there should be no spaces around separators
+        assert ": " not in compressed
+        assert ", " not in compressed
+
+        # Should be valid JSON
+        import json
+
+        parsed = json.loads(compressed)
+        assert parsed == data
+
+    def test_abbreviate_text(self):
+        """Test text abbreviation."""
+        optimizer = PromptOptimizer()
+
+        text = "The current price is high and volume is increasing."
+        abbreviated = optimizer.abbreviate_text(text)
+
+        # Should contain abbreviations
+        assert "cur" in abbreviated or "P" in abbreviated
+        assert len(abbreviated) <= len(text)
+
+    def test_abbreviate_text_aggressive(self):
+        """Test aggressive text abbreviation."""
+        optimizer = PromptOptimizer()
+
+        text = "The price is increasing and the volume is high."
+        abbreviated = optimizer.abbreviate_text(text, aggressive=True)
+
+        # Should be shorter
+        assert len(abbreviated) < len(text)
+
+        # Should have removed articles
+        assert "the" not in abbreviated.lower()
+
+    def test_build_compressed_prompt(self):
+        """Test compressed prompt building."""
+        optimizer = PromptOptimizer()
+
+        market_data = {
+            "stock_code": "005930",
+            "current_price": 75000,
+            "market_name": "Korean stock market",
+        }
+
+        prompt = optimizer.build_compressed_prompt(market_data)
+
+        # Should be much shorter than original
+        assert len(prompt) < 300
+        assert "005930" in prompt
+        assert "75000" in prompt
+
+    def test_build_compressed_prompt_no_instructions(self):
+        """Test compressed prompt without instructions."""
+        optimizer = PromptOptimizer()
+
+        market_data = {
+            "stock_code": "AAPL",
+            "current_price": 150.5,
+            "market_name": "United States",
+        }
+
+        prompt = optimizer.build_compressed_prompt(market_data, include_instructions=False)
+
+        # Should be very short (data only)
+        assert len(prompt) < 100
+        assert "AAPL" in prompt
+
+    def test_truncate_context(self):
+        """Test context truncation."""
+        optimizer = PromptOptimizer()
+
+        context = {
+            "price": 100.5,
+            "volume": 1000000,
+            "sentiment": 0.8,
+            "extra_data": "Some long text that should be truncated",
+        }
+
+        # Truncate to small budget
+        truncated = optimizer.truncate_context(context, max_tokens=10)
+
+        # Should have fewer keys
+        assert len(truncated) <= len(context)
+
+    def test_truncate_context_with_priority(self):
+        """Test context truncation with priority keys."""
+        optimizer = PromptOptimizer()
+
+        context = {
+            "price": 100.5,
+            "volume": 1000000,
+            "sentiment": 0.8,
+            "extra_data": "Some data",
+        }
+
+        priority_keys = ["price", "sentiment"]
+        truncated = optimizer.truncate_context(context, max_tokens=20, priority_keys=priority_keys)
+
+        # Priority keys should be included
+        assert "price" in truncated
+        assert "sentiment" in truncated
+
+    def test_calculate_compression_ratio(self):
+        """Test compression ratio calculation."""
+        optimizer = PromptOptimizer()
+
+        original = "This is a very long piece of text that should be compressed significantly."
+        compressed = "Short text"
+
+        ratio = optimizer.calculate_compression_ratio(original, compressed)
+
+        # Ratio should be > 1 (original is longer)
+        assert ratio > 1.0
+
+
+# ============================================================================
+# Context Selector Tests
+# ============================================================================
+
+
+class TestContextSelector:
+    """Tests for ContextSelector."""
+
+    @pytest.fixture
+    def store(self):
+        """Create in-memory ContextStore."""
+        conn = sqlite3.connect(":memory:")
+        # Create tables
+        conn.execute(
+            """
+            CREATE TABLE context_metadata (
+                layer TEXT PRIMARY KEY,
+                description TEXT,
+                retention_days INTEGER,
+                aggregation_source TEXT
+            )
+            """
+        )
+        conn.execute(
+            """
+            CREATE TABLE contexts (
+                layer TEXT,
+                timeframe TEXT,
+                key TEXT,
+                value TEXT,
+                created_at TEXT,
+                updated_at TEXT,
+                PRIMARY KEY (layer, timeframe, key)
+            )
+            """
+        )
+        conn.commit()
+        return ContextStore(conn)
+
+    def test_select_layers_normal(self, store):
+        """Test layer selection for normal decisions."""
+        selector = ContextSelector(store)
+
+        layers = selector.select_layers(DecisionType.NORMAL)
+
+        # Should only select L7 (real-time)
+        assert layers == [ContextLayer.L7_REALTIME]
+
+    def test_select_layers_strategic(self, store):
+        """Test layer selection for strategic decisions."""
+        selector = ContextSelector(store)
+
+        layers = selector.select_layers(DecisionType.STRATEGIC)
+
+        # Should select L7 + L6 + L5
+        assert ContextLayer.L7_REALTIME in layers
+        assert ContextLayer.L6_DAILY in layers
+        assert ContextLayer.L5_WEEKLY in layers
+        assert len(layers) == 3
+
+    def test_select_layers_major_event(self, store):
+        """Test layer selection for major events."""
+        selector = ContextSelector(store)
+
+        layers = selector.select_layers(DecisionType.MAJOR_EVENT)
+
+        # Should select all layers
+        assert len(layers) == 7
+        assert ContextLayer.L1_LEGACY in layers
+        assert ContextLayer.L7_REALTIME in layers
+
+    def test_score_layer_relevance(self, store):
+        """Test layer relevance scoring."""
+        selector = ContextSelector(store)
+
+        # Add some data first so scores aren't penalized
+        store.set_context(ContextLayer.L7_REALTIME, "2026-02-04", "price", 100.5)
+        store.set_context(ContextLayer.L1_LEGACY, "legacy", "lesson", "test")
+
+        # L7 should have high score for normal decisions
+        score = selector.score_layer_relevance(ContextLayer.L7_REALTIME, DecisionType.NORMAL)
+        assert score == 1.0
+
+        # L1 should have low score for normal decisions
+        score = selector.score_layer_relevance(ContextLayer.L1_LEGACY, DecisionType.NORMAL)
+        assert score == 0.0
+
+        # L1 should have high score for major events
+        score = selector.score_layer_relevance(ContextLayer.L1_LEGACY, DecisionType.MAJOR_EVENT)
+        assert score == 1.0
+
+    def test_select_with_scoring(self, store):
+        """Test selection with relevance scoring."""
+        selector = ContextSelector(store)
+
+        # Add data so layers aren't penalized
+        store.set_context(ContextLayer.L7_REALTIME, "2026-02-04", "price", 100.5)
+
+        selection = selector.select_with_scoring(DecisionType.NORMAL, min_score=0.5)
+
+        # Should only select high-relevance layers
+        assert len(selection.layers) >= 1
+        assert ContextLayer.L7_REALTIME in selection.layers
+        assert all(selection.relevance_scores[layer] >= 0.5 for layer in selection.layers)
+
+    def test_get_context_data(self, store):
+        """Test context data retrieval."""
+        selector = ContextSelector(store)
+
+        # Add some test data
+        store.set_context(ContextLayer.L7_REALTIME, "2026-02-04", "price", 100.5)
+        store.set_context(ContextLayer.L7_REALTIME, "2026-02-04", "volume", 1000000)
+
+        context_data = selector.get_context_data([ContextLayer.L7_REALTIME])
+
+        # Should retrieve data
+        assert "L7_REALTIME" in context_data
+        assert "price" in context_data["L7_REALTIME"]
+        assert context_data["L7_REALTIME"]["price"] == 100.5
+
+    def test_estimate_context_tokens(self, store):
+        """Test context token estimation."""
+        selector = ContextSelector(store)
+
+        context_data = {
+            "L7_REALTIME": {"price": 100.5, "volume": 1000000},
+            "L6_DAILY": {"avg_price": 99.8, "avg_volume": 950000},
+        }
+
+        tokens = selector.estimate_context_tokens(context_data)
+
+        # Should estimate tokens
+        assert tokens > 0
+
+    def test_optimize_context_for_budget(self, store):
+        """Test context optimization for token budget."""
+        selector = ContextSelector(store)
+
+        # Add test data
+        store.set_context(ContextLayer.L7_REALTIME, "2026-02-04", "price", 100.5)
+
+        # Get optimized context within budget
+        context = selector.optimize_context_for_budget(DecisionType.NORMAL, max_tokens=50)
+
+        # Should return data within budget
+        tokens = selector.estimate_context_tokens(context)
+        assert tokens <= 50
+
+
+# ============================================================================
+# Context Summarizer Tests
+# ============================================================================
+
+
+class TestContextSummarizer:
+    """Tests for ContextSummarizer."""
+
+    @pytest.fixture
+    def store(self):
+        """Create in-memory ContextStore."""
+        conn = sqlite3.connect(":memory:")
+        conn.execute(
+            """
+            CREATE TABLE context_metadata (
+                layer TEXT PRIMARY KEY,
+                description TEXT,
+                retention_days INTEGER,
+                aggregation_source TEXT
+            )
+            """
+        )
+        conn.execute(
+            """
+            CREATE TABLE contexts (
+                layer TEXT,
+                timeframe TEXT,
+                key TEXT,
+                value TEXT,
+                created_at TEXT,
+                updated_at TEXT,
+                PRIMARY KEY (layer, timeframe, key)
+            )
+            """
+        )
+        conn.commit()
+        return ContextStore(conn)
+
+    def test_summarize_numeric_values(self, store):
+        """Test numeric value summarization."""
+        summarizer = ContextSummarizer(store)
+
+        values = [10.0, 20.0, 30.0, 40.0, 50.0]
+        stats = summarizer.summarize_numeric_values(values)
+
+        assert isinstance(stats, SummaryStats)
+        assert stats.count == 5
+        assert stats.mean == 30.0
+        assert stats.min == 10.0
+        assert stats.max == 50.0
+        assert stats.std is not None
+
+    def test_summarize_numeric_values_trend(self, store):
+        """Test trend detection in numeric values."""
+        summarizer = ContextSummarizer(store)
+
+        # Uptrend
+        values_up = [10.0, 15.0, 20.0, 25.0, 30.0, 35.0]
+        stats_up = summarizer.summarize_numeric_values(values_up)
+        assert stats_up.trend == "up"
+
+        # Downtrend
+        values_down = [35.0, 30.0, 25.0, 20.0, 15.0, 10.0]
+        stats_down = summarizer.summarize_numeric_values(values_down)
+        assert stats_down.trend == "down"
+
+        # Flat
+        values_flat = [20.0, 20.1, 19.9, 20.0, 20.1, 19.9]
+        stats_flat = summarizer.summarize_numeric_values(values_flat)
+        assert stats_flat.trend == "flat"
+
+    def test_summarize_layer(self, store):
+        """Test layer summarization."""
+        summarizer = ContextSummarizer(store)
+
+        # Add test data
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "price", 100.5)
+        store.set_context(ContextLayer.L6_DAILY, "2026-02-04", "volume", 1000000)
+
+        summary = summarizer.summarize_layer(ContextLayer.L6_DAILY)
+
+        # Should have summary
+        assert "total_entries" in summary
+        assert summary["total_entries"] > 0
+
+    def test_create_compact_summary(self, store):
+        """Test compact summary creation."""
+        summarizer = ContextSummarizer(store)
+
+        # Add test data
+        store.set_context(ContextLayer.L7_REALTIME, "2026-02-04", "price", 100.5)
+
+        layers = [ContextLayer.L7_REALTIME, ContextLayer.L6_DAILY]
+        summary = summarizer.create_compact_summary(layers, top_n_metrics=3)
+
+        # Should have summaries for layers
+        assert "L7_REALTIME" in summary
+
+    def test_format_summary_for_prompt(self, store):
+        """Test summary formatting for prompt."""
+        summarizer = ContextSummarizer(store)
+
+        summary = {
+            "L7_REALTIME": {
+                "price": {"avg": 100.5, "trend": "up"},
+                "volume": {"avg": 1000000, "trend": "flat"},
+            }
+        }
+
+        formatted = summarizer.format_summary_for_prompt(summary)
+
+        # Should be formatted string
+        assert isinstance(formatted, str)
+        assert "L7_REALTIME" in formatted
+        assert "100.5" in formatted or "100.50" in formatted
+
+
+# ============================================================================
+# Decision Cache Tests
+# ============================================================================
+
+
+class TestDecisionCache:
+    """Tests for DecisionCache."""
+
+    def test_cache_init(self):
+        """Test cache initialization."""
+        cache = DecisionCache(ttl_seconds=60, max_size=100)
+
+        assert cache.ttl_seconds == 60
+        assert cache.max_size == 100
+
+    def test_cache_miss(self):
+        """Test cache miss."""
+        cache = DecisionCache()
+
+        market_data = {"stock_code": "005930", "current_price": 75000}
+
+        decision = cache.get(market_data)
+
+        # Should be None (cache miss)
+        assert decision is None
+
+        metrics = cache.get_metrics()
+        assert metrics.cache_misses == 1
+        assert metrics.cache_hits == 0
+
+    def test_cache_hit(self):
+        """Test cache hit."""
+        cache = DecisionCache()
+
+        market_data = {"stock_code": "005930", "current_price": 75000}
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+
+        # Set cache
+        cache.set(market_data, decision)
+
+        # Get from cache
+        cached = cache.get(market_data)
+
+        assert cached is not None
+        assert cached.action == "HOLD"
+        assert cached.confidence == 50
+
+        metrics = cache.get_metrics()
+        assert metrics.cache_hits == 1
+
+    def test_cache_ttl_expiration(self):
+        """Test cache TTL expiration."""
+        cache = DecisionCache(ttl_seconds=1)  # 1 second TTL
+
+        market_data = {"stock_code": "005930", "current_price": 75000}
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+
+        # Set cache
+        cache.set(market_data, decision)
+
+        # Should hit immediately
+        cached = cache.get(market_data)
+        assert cached is not None
+
+        # Wait for expiration
+        time.sleep(1.1)
+
+        # Should miss after expiration
+        cached = cache.get(market_data)
+        assert cached is None
+
+    def test_cache_max_size(self):
+        """Test cache max size eviction."""
+        cache = DecisionCache(max_size=2)
+
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+
+        # Add 3 entries (exceeds max_size)
+        for i in range(3):
+            market_data = {"stock_code": f"00{i}", "current_price": 1000 * i}
+            cache.set(market_data, decision)
+
+        metrics = cache.get_metrics()
+
+        # Should have evicted 1 entry
+        assert metrics.total_entries == 2
+        assert metrics.evictions == 1
+
+    def test_invalidate_all(self):
+        """Test invalidate all cache entries."""
+        cache = DecisionCache()
+
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+
+        # Add entries
+        for i in range(3):
+            market_data = {"stock_code": f"00{i}", "current_price": 1000}
+            cache.set(market_data, decision)
+
+        # Invalidate all
+        count = cache.invalidate()
+
+        assert count == 3
+
+        metrics = cache.get_metrics()
+        assert metrics.total_entries == 0
+
+    def test_invalidate_by_stock(self):
+        """Test invalidate cache by stock code."""
+        cache = DecisionCache()
+
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+
+        # Add entries for different stocks
+        cache.set({"stock_code": "005930", "current_price": 75000}, decision)
+        cache.set({"stock_code": "000660", "current_price": 50000}, decision)
+
+        # Invalidate specific stock
+        count = cache.invalidate("005930")
+
+        assert count >= 1
+
+        # Other stock should still be cached
+        cached = cache.get({"stock_code": "000660", "current_price": 50000})
+        assert cached is not None
+
+    def test_cleanup_expired(self):
+        """Test cleanup of expired entries."""
+        cache = DecisionCache(ttl_seconds=1)
+
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+
+        # Add entry
+        cache.set({"stock_code": "005930", "current_price": 75000}, decision)
+
+        # Wait for expiration
+        time.sleep(1.1)
+
+        # Cleanup
+        count = cache.cleanup_expired()
+
+        assert count == 1
+
+        metrics = cache.get_metrics()
+        assert metrics.total_entries == 0
+
+    def test_should_cache_decision(self):
+        """Test decision caching criteria."""
+        cache = DecisionCache()
+
+        # HOLD decisions should be cached
+        hold_decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+        assert cache.should_cache_decision(hold_decision) is True
+
+        # High confidence BUY should be cached
+        buy_decision = TradeDecision(action="BUY", confidence=95, rationale="Test")
+        assert cache.should_cache_decision(buy_decision) is True
+
+        # Low confidence BUY should not be cached
+        low_conf_buy = TradeDecision(action="BUY", confidence=60, rationale="Test")
+        assert cache.should_cache_decision(low_conf_buy) is False
+
+    def test_cache_hit_rate(self):
+        """Test cache hit rate calculation."""
+        cache = DecisionCache()
+
+        decision = TradeDecision(action="HOLD", confidence=50, rationale="Test")
+        market_data = {"stock_code": "005930", "current_price": 75000}
+
+        # First request (miss)
+        cache.get(market_data)
+
+        # Set cache
+        cache.set(market_data, decision)
+
+        # Second request (hit)
+        cache.get(market_data)
+
+        # Third request (hit)
+        cache.get(market_data)
+
+        metrics = cache.get_metrics()
+
+        # 1 miss, 2 hits out of 3 requests
+        assert metrics.total_requests == 3
+        assert metrics.cache_hits == 2
+        assert metrics.cache_misses == 1
+        assert metrics.hit_rate == pytest.approx(2 / 3)
+
+    def test_reset_metrics(self):
+        """Test metrics reset."""
+        cache = DecisionCache()
+
+        market_data = {"stock_code": "005930", "current_price": 75000}
+
+        # Generate some activity
+        cache.get(market_data)
+        cache.get(market_data)
+
+        # Reset
+        cache.reset_metrics()
+
+        metrics = cache.get_metrics()
+        assert metrics.total_requests == 0
+        assert metrics.cache_hits == 0
+        assert metrics.cache_misses == 0

tests/test_volatility.py

@@ -0,0 +1,511 @@
+"""Tests for volatility analysis and market scanning."""
+
+from __future__ import annotations
+
+import sqlite3
+from typing import Any
+from unittest.mock import AsyncMock
+
+import pytest
+
+from src.analysis.scanner import MarketScanner, ScanResult
+from src.analysis.volatility import VolatilityAnalyzer, VolatilityMetrics
+from src.broker.kis_api import KISBroker
+from src.broker.overseas import OverseasBroker
+from src.config import Settings
+from src.context.layer import ContextLayer
+from src.context.store import ContextStore
+from src.db import init_db
+from src.markets.schedule import MARKETS
+
+
+@pytest.fixture
+def db_conn() -> sqlite3.Connection:
+    """Provide an in-memory database connection."""
+    return init_db(":memory:")
+
+
+@pytest.fixture
+def context_store(db_conn: sqlite3.Connection) -> ContextStore:
+    """Provide a ContextStore instance."""
+    return ContextStore(db_conn)
+
+
+@pytest.fixture
+def volatility_analyzer() -> VolatilityAnalyzer:
+    """Provide a VolatilityAnalyzer instance."""
+    return VolatilityAnalyzer(min_volume_surge=2.0, min_price_change=1.0)
+
+
+@pytest.fixture
+def mock_settings() -> Settings:
+    """Provide mock settings for broker initialization."""
+    return Settings(
+        KIS_APP_KEY="test_key",
+        KIS_APP_SECRET="test_secret",
+        KIS_ACCOUNT_NO="12345678-01",
+        GEMINI_API_KEY="test_gemini_key",
+    )
+
+
+@pytest.fixture
+def mock_broker(mock_settings: Settings) -> KISBroker:
+    """Provide a mock KIS broker."""
+    broker = KISBroker(mock_settings)
+    broker.get_orderbook = AsyncMock()  # type: ignore[method-assign]
+    return broker
+
+
+@pytest.fixture
+def mock_overseas_broker(mock_broker: KISBroker) -> OverseasBroker:
+    """Provide a mock overseas broker."""
+    overseas = OverseasBroker(mock_broker)
+    overseas.get_overseas_price = AsyncMock()  # type: ignore[method-assign]
+    return overseas
+
+
+class TestVolatilityAnalyzer:
+    """Test suite for VolatilityAnalyzer."""
+
+    def test_calculate_atr(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test ATR calculation."""
+        high_prices = [110.0, 112.0, 115.0, 113.0, 116.0] + [120.0] * 10
+        low_prices = [105.0, 107.0, 110.0, 108.0, 111.0] + [115.0] * 10
+        close_prices = [108.0, 110.0, 112.0, 111.0, 114.0] + [118.0] * 10
+
+        atr = volatility_analyzer.calculate_atr(high_prices, low_prices, close_prices, period=14)
+
+        assert atr > 0.0
+        # ATR should be roughly the average true range
+        assert 3.0 <= atr <= 6.0
+
+    def test_calculate_atr_insufficient_data(
+        self, volatility_analyzer: VolatilityAnalyzer
+    ) -> None:
+        """Test ATR with insufficient data returns 0."""
+        high_prices = [110.0, 112.0]
+        low_prices = [105.0, 107.0]
+        close_prices = [108.0, 110.0]
+
+        atr = volatility_analyzer.calculate_atr(high_prices, low_prices, close_prices, period=14)
+
+        assert atr == 0.0
+
+    def test_calculate_price_change(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test price change percentage calculation."""
+        # 10% increase
+        change = volatility_analyzer.calculate_price_change(110.0, 100.0)
+        assert change == pytest.approx(10.0)
+
+        # 5% decrease
+        change = volatility_analyzer.calculate_price_change(95.0, 100.0)
+        assert change == pytest.approx(-5.0)
+
+        # Zero past price
+        change = volatility_analyzer.calculate_price_change(100.0, 0.0)
+        assert change == 0.0
+
+    def test_calculate_volume_surge(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test volume surge ratio calculation."""
+        # 2x surge
+        surge = volatility_analyzer.calculate_volume_surge(2000.0, 1000.0)
+        assert surge == pytest.approx(2.0)
+
+        # Below average
+        surge = volatility_analyzer.calculate_volume_surge(500.0, 1000.0)
+        assert surge == pytest.approx(0.5)
+
+        # Zero average
+        surge = volatility_analyzer.calculate_volume_surge(1000.0, 0.0)
+        assert surge == 1.0
+
+    def test_calculate_pv_divergence_bullish(
+        self, volatility_analyzer: VolatilityAnalyzer
+    ) -> None:
+        """Test bullish price-volume divergence."""
+        # Price up + Volume up = bullish
+        divergence = volatility_analyzer.calculate_pv_divergence(5.0, 2.0)
+        assert divergence > 0.0
+
+    def test_calculate_pv_divergence_bearish(
+        self, volatility_analyzer: VolatilityAnalyzer
+    ) -> None:
+        """Test bearish price-volume divergence."""
+        # Price up + Volume down = bearish divergence
+        divergence = volatility_analyzer.calculate_pv_divergence(5.0, 0.5)
+        assert divergence < 0.0
+
+    def test_calculate_pv_divergence_selling_pressure(
+        self, volatility_analyzer: VolatilityAnalyzer
+    ) -> None:
+        """Test selling pressure detection."""
+        # Price down + Volume up = selling pressure
+        divergence = volatility_analyzer.calculate_pv_divergence(-5.0, 2.0)
+        assert divergence < 0.0
+
+    def test_calculate_momentum_score(
+        self, volatility_analyzer: VolatilityAnalyzer
+    ) -> None:
+        """Test momentum score calculation."""
+        score = volatility_analyzer.calculate_momentum_score(
+            price_change_1m=5.0,
+            price_change_5m=3.0,
+            price_change_15m=2.0,
+            volume_surge=2.5,
+            atr=1.5,
+            current_price=100.0,
+        )
+
+        assert 0.0 <= score <= 100.0
+        assert score > 50.0  # Should be high for strong positive momentum
+
+    def test_calculate_momentum_score_negative(
+        self, volatility_analyzer: VolatilityAnalyzer
+    ) -> None:
+        """Test momentum score with negative price changes."""
+        score = volatility_analyzer.calculate_momentum_score(
+            price_change_1m=-5.0,
+            price_change_5m=-3.0,
+            price_change_15m=-2.0,
+            volume_surge=1.0,
+            atr=1.0,
+            current_price=100.0,
+        )
+
+        assert 0.0 <= score <= 100.0
+        assert score < 50.0  # Should be low for negative momentum
+
+    def test_analyze(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test full analysis of a stock."""
+        orderbook_data = {
+            "output1": {
+                "stck_prpr": "50000",
+                "acml_vol": "1000000",
+            }
+        }
+
+        price_history = {
+            "high": [51000.0] * 20,
+            "low": [49000.0] * 20,
+            "close": [48000.0] + [50000.0] * 19,
+            "volume": [500000.0] * 20,
+        }
+
+        metrics = volatility_analyzer.analyze("005930", orderbook_data, price_history)
+
+        assert metrics.stock_code == "005930"
+        assert metrics.current_price == 50000.0
+        assert metrics.atr > 0.0
+        assert metrics.volume_surge == pytest.approx(2.0)  # 1M / 500K
+        assert 0.0 <= metrics.momentum_score <= 100.0
+
+    def test_is_breakout(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test breakout detection."""
+        # Strong breakout
+        metrics = VolatilityMetrics(
+            stock_code="005930",
+            current_price=50000.0,
+            atr=500.0,
+            price_change_1m=2.5,
+            price_change_5m=3.0,
+            price_change_15m=4.0,
+            volume_surge=3.0,
+            pv_divergence=50.0,
+            momentum_score=85.0,
+        )
+
+        assert volatility_analyzer.is_breakout(metrics) is True
+
+    def test_is_breakout_no_volume(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test that breakout requires volume confirmation."""
+        # Price up but no volume = not a real breakout
+        metrics = VolatilityMetrics(
+            stock_code="005930",
+            current_price=50000.0,
+            atr=500.0,
+            price_change_1m=2.5,
+            price_change_5m=3.0,
+            price_change_15m=4.0,
+            volume_surge=1.2,  # Below threshold
+            pv_divergence=10.0,
+            momentum_score=70.0,
+        )
+
+        assert volatility_analyzer.is_breakout(metrics) is False
+
+    def test_is_breakdown(self, volatility_analyzer: VolatilityAnalyzer) -> None:
+        """Test breakdown detection."""
+        # Strong breakdown
+        metrics = VolatilityMetrics(
+            stock_code="005930",
+            current_price=50000.0,
+            atr=500.0,
+            price_change_1m=-2.5,
+            price_change_5m=-3.0,
+            price_change_15m=-4.0,
+            volume_surge=3.0,
+            pv_divergence=-50.0,
+            momentum_score=15.0,
+        )
+
+        assert volatility_analyzer.is_breakdown(metrics) is True
+
+    def test_volatility_metrics_repr(self) -> None:
+        """Test VolatilityMetrics string representation."""
+        metrics = VolatilityMetrics(
+            stock_code="005930",
+            current_price=50000.0,
+            atr=500.0,
+            price_change_1m=2.5,
+            price_change_5m=3.0,
+            price_change_15m=4.0,
+            volume_surge=3.0,
+            pv_divergence=50.0,
+            momentum_score=85.0,
+        )
+
+        repr_str = repr(metrics)
+        assert "005930" in repr_str
+        assert "50000.00" in repr_str
+        assert "2.50%" in repr_str
+
+
+class TestMarketScanner:
+    """Test suite for MarketScanner."""
+
+    @pytest.fixture
+    def scanner(
+        self,
+        mock_broker: KISBroker,
+        mock_overseas_broker: OverseasBroker,
+        volatility_analyzer: VolatilityAnalyzer,
+        context_store: ContextStore,
+    ) -> MarketScanner:
+        """Provide a MarketScanner instance."""
+        return MarketScanner(
+            broker=mock_broker,
+            overseas_broker=mock_overseas_broker,
+            volatility_analyzer=volatility_analyzer,
+            context_store=context_store,
+            top_n=5,
+        )
+
+    @pytest.mark.asyncio
+    async def test_scan_stock_domestic(
+        self,
+        scanner: MarketScanner,
+        mock_broker: KISBroker,
+        context_store: ContextStore,
+    ) -> None:
+        """Test scanning a domestic stock."""
+        mock_broker.get_orderbook.return_value = {
+            "output1": {
+                "stck_prpr": "50000",
+                "acml_vol": "1000000",
+            }
+        }
+
+        market = MARKETS["KR"]
+        metrics = await scanner.scan_stock("005930", market)
+
+        assert metrics is not None
+        assert metrics.stock_code == "005930"
+        assert metrics.current_price == 50000.0
+
+        # Verify L7 context was stored
+        latest_timeframe = context_store.get_latest_timeframe(ContextLayer.L7_REALTIME)
+        assert latest_timeframe is not None
+
+    @pytest.mark.asyncio
+    async def test_scan_stock_overseas(
+        self,
+        scanner: MarketScanner,
+        mock_overseas_broker: OverseasBroker,
+        context_store: ContextStore,
+    ) -> None:
+        """Test scanning an overseas stock."""
+        mock_overseas_broker.get_overseas_price.return_value = {
+            "output": {
+                "last": "150.50",
+                "tvol": "5000000",
+            }
+        }
+
+        market = MARKETS["US_NASDAQ"]
+        metrics = await scanner.scan_stock("AAPL", market)
+
+        assert metrics is not None
+        assert metrics.stock_code == "AAPL"
+        assert metrics.current_price == 150.50
+
+    @pytest.mark.asyncio
+    async def test_scan_stock_error_handling(
+        self,
+        scanner: MarketScanner,
+        mock_broker: KISBroker,
+    ) -> None:
+        """Test that scan_stock handles errors gracefully."""
+        mock_broker.get_orderbook.side_effect = Exception("Network error")
+
+        market = MARKETS["KR"]
+        metrics = await scanner.scan_stock("005930", market)
+
+        assert metrics is None  # Should return None on error, not crash
+
+    @pytest.mark.asyncio
+    async def test_scan_market(
+        self,
+        scanner: MarketScanner,
+        mock_broker: KISBroker,
+        context_store: ContextStore,
+    ) -> None:
+        """Test scanning a full market."""
+
+        def mock_orderbook(stock_code: str) -> dict[str, Any]:
+            """Generate mock orderbook with varying prices."""
+            base_price = int(stock_code) if stock_code.isdigit() else 50000
+            return {
+                "output1": {
+                    "stck_prpr": str(base_price),
+                    "acml_vol": str(base_price * 20),  # Volume proportional to price
+                }
+            }
+
+        mock_broker.get_orderbook.side_effect = mock_orderbook
+
+        market = MARKETS["KR"]
+        stock_codes = ["005930", "000660", "035420"]
+
+        result = await scanner.scan_market(market, stock_codes)
+
+        assert result.market_code == "KR"
+        assert result.total_scanned == 3
+        assert len(result.top_movers) <= 5
+        assert all(isinstance(m, VolatilityMetrics) for m in result.top_movers)
+
+        # Verify scan result was stored in L7
+        latest_timeframe = context_store.get_latest_timeframe(ContextLayer.L7_REALTIME)
+        assert latest_timeframe is not None
+        scan_result = context_store.get_context(
+            ContextLayer.L7_REALTIME,
+            latest_timeframe,
+            "KR_scan_result",
+        )
+        assert scan_result is not None
+        assert scan_result["total_scanned"] == 3
+
+    @pytest.mark.asyncio
+    async def test_scan_market_with_breakouts(
+        self,
+        scanner: MarketScanner,
+        mock_broker: KISBroker,
+    ) -> None:
+        """Test that scan detects breakouts."""
+        # Mock strong price increase with volume
+        mock_broker.get_orderbook.return_value = {
+            "output1": {
+                "stck_prpr": "55000",  # High price
+                "acml_vol": "5000000",  # High volume
+            }
+        }
+
+        market = MARKETS["KR"]
+        stock_codes = ["005930"]
+
+        result = await scanner.scan_market(market, stock_codes)
+
+        # With high volume and price, might detect breakouts
+        # (depends on price history which is empty in this test)
+        assert isinstance(result.breakouts, list)
+        assert isinstance(result.breakdowns, list)
+
+    def test_get_updated_watchlist(self, scanner: MarketScanner) -> None:
+        """Test watchlist update logic."""
+        current_watchlist = ["005930", "000660", "035420"]
+
+        # Create scan result with new leaders
+        top_movers = [
+            VolatilityMetrics("005930", 50000, 500, 2.0, 3.0, 4.0, 3.0, 50.0, 90.0),
+            VolatilityMetrics("005380", 48000, 480, 1.8, 2.5, 3.0, 2.8, 45.0, 85.0),
+            VolatilityMetrics("005490", 46000, 460, 1.5, 2.0, 2.5, 2.5, 40.0, 80.0),
+        ]
+
+        scan_result = ScanResult(
+            market_code="KR",
+            timestamp="2026-02-04T10:00:00",
+            total_scanned=10,
+            top_movers=top_movers,
+            breakouts=["005380"],
+            breakdowns=[],
+        )
+
+        updated = scanner.get_updated_watchlist(
+            current_watchlist,
+            scan_result,
+            max_replacements=2,
+        )
+
+        assert "005930" in updated  # Should keep existing top mover
+        assert "005380" in updated  # Should add new leader
+        assert len(updated) == len(current_watchlist)  # Should maintain size
+
+    def test_get_updated_watchlist_all_keepers(self, scanner: MarketScanner) -> None:
+        """Test watchlist when all current stocks are still top movers."""
+        current_watchlist = ["005930", "000660", "035420"]
+
+        top_movers = [
+            VolatilityMetrics("005930", 50000, 500, 2.0, 3.0, 4.0, 3.0, 50.0, 90.0),
+            VolatilityMetrics("000660", 48000, 480, 1.8, 2.5, 3.0, 2.8, 45.0, 85.0),
+            VolatilityMetrics("035420", 46000, 460, 1.5, 2.0, 2.5, 2.5, 40.0, 80.0),
+        ]
+
+        scan_result = ScanResult(
+            market_code="KR",
+            timestamp="2026-02-04T10:00:00",
+            total_scanned=10,
+            top_movers=top_movers,
+            breakouts=[],
+            breakdowns=[],
+        )
+
+        updated = scanner.get_updated_watchlist(
+            current_watchlist,
+            scan_result,
+            max_replacements=2,
+        )
+
+        # Should keep all current stocks since they're all in top movers
+        assert set(updated) == set(current_watchlist)
+
+    def test_get_updated_watchlist_max_replacements(
+        self, scanner: MarketScanner
+    ) -> None:
+        """Test that max_replacements limit is respected."""
+        current_watchlist = ["000660", "035420", "005490"]
+
+        # All new leaders (none in current watchlist)
+        top_movers = [
+            VolatilityMetrics("005930", 50000, 500, 2.0, 3.0, 4.0, 3.0, 50.0, 90.0),
+            VolatilityMetrics("005380", 48000, 480, 1.8, 2.5, 3.0, 2.8, 45.0, 85.0),
+            VolatilityMetrics("035720", 46000, 460, 1.5, 2.0, 2.5, 2.5, 40.0, 80.0),
+        ]
+
+        scan_result = ScanResult(
+            market_code="KR",
+            timestamp="2026-02-04T10:00:00",
+            total_scanned=10,
+            top_movers=top_movers,
+            breakouts=[],
+            breakdowns=[],
+        )
+
+        updated = scanner.get_updated_watchlist(
+            current_watchlist,
+            scan_result,
+            max_replacements=1,  # Only allow 1 replacement
+        )
+
+        # Should add at most 1 new leader
+        new_additions = [code for code in updated if code not in current_watchlist]
+        assert len(new_additions) <= 1
+        assert len(updated) == len(current_watchlist)