fix: BUY 결정 전 기존 포지션 체크 추가 — 중복 매수 방지 (#191)

어제(2026-02-20) 거래 로그에서 NP 7번, KNRX 5번 중복 매수 발생.
trading_cycle()의 BUY 브랜치에 get_open_position() 체크를 추가하여
이미 보유 중인 종목은 HOLD로 전환, 재매수를 차단함.

- src/main.py: BUY 결정 직후 기존 포지션 확인 → 있으면 HOLD 변환
- tests/test_main.py: 테스트 2개 추가
  - test_buy_suppressed_when_open_position_exists
  - test_buy_proceeds_when_no_open_position

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/commands.md

@@ -192,6 +192,27 @@ When `TELEGRAM_COMMANDS_ENABLED=true` (default), the bot accepts these interacti
 
 Commands are only processed from the authorized `TELEGRAM_CHAT_ID`.
 
+## KIS API TR_ID 참조 문서
+
+**TR_ID를 추가하거나 수정할 때 반드시 공식 문서를 먼저 확인할 것.**
+
+공식 문서: `docs/한국투자증권_오픈API_전체문서_20260221_030000.xlsx`
+
+> ⚠️ 커뮤니티 블로그, GitHub 예제 등 비공식 자료의 TR_ID는 오래되거나 틀릴 수 있음.
+> 실제로 `VTTT1006U`(미국 매도 — 잘못됨)가 오랫동안 코드에 남아있던 사례가 있음 (Issue #189).
+
+### 주요 TR_ID 목록
+
+| 구분 | 모의투자 TR_ID | 실전투자 TR_ID | 시트명 |
+|------|---------------|---------------|--------|
+| 해외주식 매수 (미국) | `VTTT1002U` | `TTTT1002U` | 해외주식 주문 |
+| 해외주식 매도 (미국) | `VTTT1001U` | `TTTT1006U` | 해외주식 주문 |
+
+새로운 TR_ID가 필요할 때:
+1. 위 xlsx 파일에서 해당 거래 유형의 시트를 찾는다.
+2. 모의투자(`VTTT`) / 실전투자(`TTTT`) 컬럼을 구분하여 정확한 값을 사용한다.
+3. 코드에 출처 주석을 남긴다: `# Source: 한국투자증권_오픈API_전체문서 — '<시트명>' 시트`
+
 ## Environment Setup
 
 ```bash

docs/requirements-log.md

@@ -7,6 +7,32 @@
 
 ---
 
+## 2026-02-21
+
+### 거래 상태 확인 중 발견된 버그 (#187)
+
+- 거래 상태 점검 요청 → SELL 주문(손절/익절)이 Fat Finger에 막혀 전혀 실행 안 됨 발견
+- **#187 (Critical)**: SELL 주문에서 Fat Finger 오탐 — `order_amount/total_cash > 30%`가 SELL에도 적용되어 대형 포지션 매도 불가
+  - JELD stop-loss -6.20% → 차단, RXT take-profit +46.13% → 차단
+  - 수정: SELL은 `check_circuit_breaker`만 호출, `validate_order`(Fat Finger 포함) 미호출
+
+---
+
+## 2026-02-20
+
+### 지속적 모니터링 및 개선점 도출 (이슈 #178~#182)
+
+- Dashboard 포함해서 실행하며 간헐적 문제 모니터링 및 개선점 자동 도출 요청
+- 모니터링 결과 발견된 이슈 목록:
+  - **#178**: uvicorn 미설치 → dashboard 미작동 + 오해의 소지 있는 시작 로그 → uvicorn 설치 완료
+  - **#179 (Critical)**: 잔액 부족 주문 실패 후 매 사이클마다 무한 재시도 (MLECW 20분 이상 반복)
+  - **#180**: 다중 인스턴스 실행 시 Telegram 409 충돌
+  - **#181**: implied_rsi 공식 포화 문제 (change_rate≥12.5% → RSI=100)
+  - **#182 (Critical)**: 보유 종목이 SmartScanner 변동성 필터에 걸려 SELL 신호 미생성 → SELL 체결 0건, 잔고 소진
+- 요구사항: 모니터링 자동화 및 주기적 개선점 리포트 도출
+
+---
+
 ## 2026-02-05
 
 ### API 효율화

src/analysis/smart_scanner.py

@@ -175,7 +175,7 @@ class SmartVolatilityScanner:
                 liquidity_score = volume_rank_bonus.get(stock_code, 0.0)
                 score = min(100.0, volatility_score + liquidity_score)
                 signal = "momentum" if change_rate >= 0 else "oversold"
-                implied_rsi = max(0.0, min(100.0, 50.0 + (change_rate * 4.0)))
+                implied_rsi = max(0.0, min(100.0, 50.0 + (change_rate * 2.0)))
 
                 candidates.append(
                     ScanCandidate(
@@ -282,7 +282,7 @@ class SmartVolatilityScanner:
             liquidity_score = volume_rank_bonus.get(stock_code, 0.0)
             score = min(100.0, volatility_score + liquidity_score)
             signal = "momentum" if change_rate >= 0 else "oversold"
-            implied_rsi = max(0.0, min(100.0, 50.0 + (change_rate * 4.0)))
+            implied_rsi = max(0.0, min(100.0, 50.0 + (change_rate * 2.0)))
             candidates.append(
                 ScanCandidate(
                     stock_code=stock_code,
@@ -338,7 +338,7 @@ class SmartVolatilityScanner:
 
                 score = min(volatility_pct / 10.0, 1.0) * 100.0
                 signal = "momentum" if change_rate >= 0 else "oversold"
-                implied_rsi = max(0.0, min(100.0, 50.0 + (change_rate * 4.0)))
+                implied_rsi = max(0.0, min(100.0, 50.0 + (change_rate * 2.0)))
                 candidates.append(
                     ScanCandidate(
                         stock_code=stock_code,

src/broker/overseas.py

@@ -230,7 +230,9 @@ class OverseasBroker:
         session = self._broker._get_session()
 
         # Virtual trading TR_IDs for overseas orders
-        tr_id = "VTTT1002U" if order_type == "BUY" else "VTTT1006U"
+        # Source: 한국투자증권 오픈API 전체문서 (20260221) — '해외주식 주문' 시트
+        # VTTT1002U: 모의투자 미국 매수, VTTT1001U: 모의투자 미국 매도
+        tr_id = "VTTT1002U" if order_type == "BUY" else "VTTT1001U"
 
         body = {
             "CANO": self._broker._account_no,

src/main.py

@@ -81,6 +81,7 @@ def safe_float(value: str | float | None, default: float = 0.0) -> float:
 TRADE_INTERVAL_SECONDS = 60
 SCAN_INTERVAL_SECONDS = 60  # Scan markets every 60 seconds
 MAX_CONNECTION_RETRIES = 3
+_BUY_COOLDOWN_SECONDS = 600  # 10-minute cooldown after insufficient-balance rejection
 
 # Daily trading mode constants (for Free tier API efficiency)
 DAILY_TRADE_SESSIONS = 4  # Number of trading sessions per day
@@ -298,6 +299,7 @@ async def trading_cycle(
     stock_code: str,
     scan_candidates: dict[str, dict[str, ScanCandidate]],
     settings: Settings | None = None,
+    buy_cooldown: dict[str, float] | None = None,
 ) -> None:
     """Execute one trading cycle for a single stock."""
     cycle_start_time = asyncio.get_event_loop().time()
@@ -508,6 +510,25 @@ async def trading_cycle(
                 ),
             )
 
+    # BUY 결정 전 기존 포지션 체크 (중복 매수 방지)
+    if decision.action == "BUY":
+        existing_position = get_open_position(db_conn, stock_code, market.code)
+        if existing_position:
+            decision = TradeDecision(
+                action="HOLD",
+                confidence=decision.confidence,
+                rationale=(
+                    f"Already holding {stock_code} "
+                    f"(entry={existing_position['price']:.4f}, "
+                    f"qty={existing_position['quantity']})"
+                ),
+            )
+            logger.info(
+                "BUY suppressed for %s (%s): already holding open position",
+                stock_code,
+                market.name,
+            )
+
     if decision.action == "HOLD":
         open_position = get_open_position(db_conn, stock_code, market.code)
         if open_position:
@@ -642,13 +663,33 @@ async def trading_cycle(
             return
         order_amount = current_price * quantity
 
-        # 4. Risk check BEFORE order
+        # 4. Check BUY cooldown (set when a prior BUY failed due to insufficient balance)
+        if decision.action == "BUY" and buy_cooldown is not None:
+            cooldown_key = f"{market.code}:{stock_code}"
+            cooldown_until = buy_cooldown.get(cooldown_key, 0.0)
+            now = asyncio.get_event_loop().time()
+            if now < cooldown_until:
+                remaining = int(cooldown_until - now)
+                logger.info(
+                    "Skip BUY %s (%s): insufficient-balance cooldown active (%ds remaining)",
+                    stock_code,
+                    market.name,
+                    remaining,
+                )
+                return
+
+        # 5a. Risk check BEFORE order
+        # SELL orders do not consume cash (they receive it), so fat-finger check
+        # is skipped for SELLs — only circuit breaker applies.
         try:
-            risk.validate_order(
-                current_pnl_pct=pnl_pct,
-                order_amount=order_amount,
-                total_cash=total_cash,
-            )
+            if decision.action == "SELL":
+                risk.check_circuit_breaker(pnl_pct)
+            else:
+                risk.validate_order(
+                    current_pnl_pct=pnl_pct,
+                    order_amount=order_amount,
+                    total_cash=total_cash,
+                )
         except FatFingerRejected as exc:
             try:
                 await telegram.notify_fat_finger(
@@ -690,12 +731,24 @@ async def trading_cycle(
             # Check if KIS rejected the order (rt_cd != "0")
             if result.get("rt_cd", "") != "0":
                 order_succeeded = False
+                msg1 = result.get("msg1") or ""
                 logger.warning(
                     "Overseas order not accepted for %s: rt_cd=%s msg=%s",
                     stock_code,
                     result.get("rt_cd"),
-                    result.get("msg1"),
+                    msg1,
                 )
+                # Set BUY cooldown when the rejection is due to insufficient balance
+                if decision.action == "BUY" and buy_cooldown is not None and "주문가능금액" in msg1:
+                    cooldown_key = f"{market.code}:{stock_code}"
+                    buy_cooldown[cooldown_key] = (
+                        asyncio.get_event_loop().time() + _BUY_COOLDOWN_SECONDS
+                    )
+                    logger.info(
+                        "BUY cooldown set for %s: %.0fs (insufficient balance)",
+                        stock_code,
+                        _BUY_COOLDOWN_SECONDS,
+                    )
         logger.info("Order result: %s", result.get("msg1", "OK"))
 
         # 5.5. Notify trade execution (only on success)
@@ -803,6 +856,9 @@ async def run_daily_session(
 
     logger.info("Starting daily trading session for %d markets", len(open_markets))
 
+    # BUY cooldown: prevents retrying stocks rejected for insufficient balance
+    daily_buy_cooldown: dict[str, float] = {}  # "{market_code}:{stock_code}" -> expiry timestamp
+
     # Process each open market
     for market in open_markets:
         # Use market-local date for playbook keying
@@ -1075,13 +1131,33 @@ async def run_daily_session(
                     continue
                 order_amount = stock_data["current_price"] * quantity
 
+                # Check BUY cooldown (insufficient balance)
+                if decision.action == "BUY":
+                    daily_cooldown_key = f"{market.code}:{stock_code}"
+                    daily_cooldown_until = daily_buy_cooldown.get(daily_cooldown_key, 0.0)
+                    now = asyncio.get_event_loop().time()
+                    if now < daily_cooldown_until:
+                        remaining = int(daily_cooldown_until - now)
+                        logger.info(
+                            "Skip BUY %s (%s): insufficient-balance cooldown active (%ds remaining)",
+                            stock_code,
+                            market.name,
+                            remaining,
+                        )
+                        continue
+
                 # Risk check
+                # SELL orders do not consume cash (they receive it), so fat-finger
+                # check is skipped for SELLs — only circuit breaker applies.
                 try:
-                    risk.validate_order(
-                        current_pnl_pct=pnl_pct,
-                        order_amount=order_amount,
-                        total_cash=total_cash,
-                    )
+                    if decision.action == "SELL":
+                        risk.check_circuit_breaker(pnl_pct)
+                    else:
+                        risk.validate_order(
+                            current_pnl_pct=pnl_pct,
+                            order_amount=order_amount,
+                            total_cash=total_cash,
+                        )
                 except FatFingerRejected as exc:
                     try:
                         await telegram.notify_fat_finger(
@@ -1131,12 +1207,23 @@ async def run_daily_session(
                         )
                         if result.get("rt_cd", "") != "0":
                             order_succeeded = False
+                            daily_msg1 = result.get("msg1") or ""
                             logger.warning(
                                 "Overseas order not accepted for %s: rt_cd=%s msg=%s",
                                 stock_code,
                                 result.get("rt_cd"),
-                                result.get("msg1"),
+                                daily_msg1,
                             )
+                            if decision.action == "BUY" and "주문가능금액" in daily_msg1:
+                                daily_cooldown_key = f"{market.code}:{stock_code}"
+                                daily_buy_cooldown[daily_cooldown_key] = (
+                                    asyncio.get_event_loop().time() + _BUY_COOLDOWN_SECONDS
+                                )
+                                logger.info(
+                                    "BUY cooldown set for %s: %.0fs (insufficient balance)",
+                                    stock_code,
+                                    _BUY_COOLDOWN_SECONDS,
+                                )
                     logger.info("Order result: %s", result.get("msg1", "OK"))
 
                     # Notify trade execution (only on success)
@@ -1763,6 +1850,9 @@ async def run(settings: Settings) -> None:
     # Active stocks per market (dynamically discovered by scanner)
     active_stocks: dict[str, list[str]] = {}  # market_code -> [stock_codes]
 
+    # BUY cooldown: prevents retrying a stock rejected for insufficient balance
+    buy_cooldown: dict[str, float] = {}  # "{market_code}:{stock_code}" -> expiry timestamp
+
     # Initialize latency control system
     criticality_assessor = CriticalityAssessor(
         critical_pnl_threshold=-2.5,  # Near circuit breaker at -3.0%
@@ -2105,6 +2195,7 @@ async def run(settings: Settings) -> None:
                                     stock_code,
                                     scan_candidates,
                                     settings,
+                                    buy_cooldown,
                                 )
                                 break  # Success — exit retry loop
                             except CircuitBreakerTripped as exc:

src/notifications/telegram_client.py

@@ -604,9 +604,19 @@ class TelegramCommandHandler:
             async with session.post(url, json=payload) as resp:
                 if resp.status != 200:
                     error_text = await resp.text()
-                    logger.error(
-                        "getUpdates API error (status=%d): %s", resp.status, error_text
-                    )
+                    if resp.status == 409:
+                        # Another bot instance is already polling — stop this poller entirely.
+                        # Retrying would keep conflicting with the other instance.
+                        self._running = False
+                        logger.warning(
+                            "Telegram conflict (409): another instance is already polling. "
+                            "Disabling Telegram commands for this process. "
+                            "Ensure only one instance of The Ouroboros is running at a time.",
+                        )
+                    else:
+                        logger.error(
+                            "getUpdates API error (status=%d): %s", resp.status, error_text
+                        )
                     return []
 
                 data = await resp.json()

tests/test_main.py

@@ -631,6 +631,119 @@ class TestTradingCycleTelegramIntegration:
         # Verify no trade notification sent
         mock_telegram.notify_trade_execution.assert_not_called()
 
+    @pytest.mark.asyncio
+    async def test_sell_skips_fat_finger_check(
+        self,
+        mock_broker: MagicMock,
+        mock_overseas_broker: MagicMock,
+        mock_scenario_engine: MagicMock,
+        mock_playbook: DayPlaybook,
+        mock_risk: MagicMock,
+        mock_db: MagicMock,
+        mock_decision_logger: MagicMock,
+        mock_context_store: MagicMock,
+        mock_criticality_assessor: MagicMock,
+        mock_telegram: MagicMock,
+        mock_market: MagicMock,
+    ) -> None:
+        """SELL orders must not be blocked by fat-finger check.
+
+        Even if position value > 30% of cash (e.g. stop-loss on a large holding
+        with low remaining cash), the SELL should proceed — only circuit breaker
+        applies to SELLs.
+        """
+        # SELL decision with held qty=100 shares @ 50,000 = 5,000,000
+        # cash = 5,000,000 → ratio = 100% which would normally trigger fat finger
+        mock_scenario_engine.evaluate = MagicMock(return_value=_make_sell_match())
+        mock_broker.get_balance = AsyncMock(
+            return_value={
+                "output1": [{"pdno": "005930", "ord_psbl_qty": "100"}],
+                "output2": [
+                    {
+                        "tot_evlu_amt": "10000000",
+                        "dnca_tot_amt": "5000000",
+                        "pchs_amt_smtl_amt": "5000000",
+                    }
+                ],
+            }
+        )
+
+        with patch("src.main.log_trade"):
+            await trading_cycle(
+                broker=mock_broker,
+                overseas_broker=mock_overseas_broker,
+                scenario_engine=mock_scenario_engine,
+                playbook=mock_playbook,
+                risk=mock_risk,
+                db_conn=mock_db,
+                decision_logger=mock_decision_logger,
+                context_store=mock_context_store,
+                criticality_assessor=mock_criticality_assessor,
+                telegram=mock_telegram,
+                market=mock_market,
+                stock_code="005930",
+                scan_candidates={},
+            )
+
+        # validate_order (which includes fat finger) must NOT be called for SELL
+        mock_risk.validate_order.assert_not_called()
+        # check_circuit_breaker MUST be called for SELL
+        mock_risk.check_circuit_breaker.assert_called_once()
+
+    @pytest.mark.asyncio
+    async def test_sell_circuit_breaker_still_applies(
+        self,
+        mock_broker: MagicMock,
+        mock_overseas_broker: MagicMock,
+        mock_scenario_engine: MagicMock,
+        mock_playbook: DayPlaybook,
+        mock_risk: MagicMock,
+        mock_db: MagicMock,
+        mock_decision_logger: MagicMock,
+        mock_context_store: MagicMock,
+        mock_criticality_assessor: MagicMock,
+        mock_telegram: MagicMock,
+        mock_market: MagicMock,
+    ) -> None:
+        """SELL orders must still respect the circuit breaker."""
+        mock_scenario_engine.evaluate = MagicMock(return_value=_make_sell_match())
+        mock_broker.get_balance = AsyncMock(
+            return_value={
+                "output1": [{"pdno": "005930", "ord_psbl_qty": "100"}],
+                "output2": [
+                    {
+                        "tot_evlu_amt": "10000000",
+                        "dnca_tot_amt": "5000000",
+                        "pchs_amt_smtl_amt": "5000000",
+                    }
+                ],
+            }
+        )
+        mock_risk.check_circuit_breaker.side_effect = CircuitBreakerTripped(
+            pnl_pct=-4.0, threshold=-3.0
+        )
+
+        with patch("src.main.log_trade"):
+            with pytest.raises(CircuitBreakerTripped):
+                await trading_cycle(
+                    broker=mock_broker,
+                    overseas_broker=mock_overseas_broker,
+                    scenario_engine=mock_scenario_engine,
+                    playbook=mock_playbook,
+                    risk=mock_risk,
+                    db_conn=mock_db,
+                    decision_logger=mock_decision_logger,
+                    context_store=mock_context_store,
+                    criticality_assessor=mock_criticality_assessor,
+                    telegram=mock_telegram,
+                    market=mock_market,
+                    stock_code="005930",
+                    scan_candidates={},
+                )
+
+        mock_risk.check_circuit_breaker.assert_called_once()
+        mock_risk.validate_order.assert_not_called()
+
 
 class TestRunFunctionTelegramIntegration:
     """Test telegram notifications in run function."""
@@ -2217,6 +2330,245 @@ def test_start_dashboard_server_returns_none_when_uvicorn_missing() -> None:
     assert thread is None
 
 
+# ---------------------------------------------------------------------------
+# BUY cooldown tests (#179)
+# ---------------------------------------------------------------------------
+
+
+class TestBuyCooldown:
+    """Tests for BUY cooldown after insufficient-balance rejection."""
+
+    @pytest.fixture
+    def mock_broker(self) -> MagicMock:
+        broker = MagicMock()
+        broker.get_current_price = AsyncMock(return_value=(100.0, 1.0, 0.0))
+        broker.get_balance = AsyncMock(
+            return_value={
+                "output2": [{"tot_evlu_amt": "1000000", "dnca_tot_amt": "500000",
+                             "pchs_amt_smtl_amt": "500000"}]
+            }
+        )
+        broker.send_order = AsyncMock(return_value={"msg1": "OK"})
+        return broker
+
+    @pytest.fixture
+    def mock_market(self) -> MagicMock:
+        market = MagicMock()
+        market.name = "Korea"
+        market.code = "KR"
+        market.exchange_code = "KRX"
+        market.is_domestic = True
+        return market
+
+    @pytest.fixture
+    def mock_overseas_market(self) -> MagicMock:
+        market = MagicMock()
+        market.name = "NASDAQ"
+        market.code = "US_NASDAQ"
+        market.exchange_code = "NAS"
+        market.is_domestic = False
+        return market
+
+    @pytest.fixture
+    def mock_overseas_broker(self) -> MagicMock:
+        broker = MagicMock()
+        broker.get_overseas_price = AsyncMock(
+            return_value={"output": {"last": "1.0", "rate": "0.0",
+                                     "high": "1.05", "low": "0.95", "tvol": "1000000"}}
+        )
+        broker.get_overseas_balance = AsyncMock(return_value={
+            "output1": [],
+            "output2": [{"frcr_dncl_amt_2": "50000", "frcr_evlu_tota": "50000",
+                         "frcr_buy_amt_smtl": "0"}],
+        })
+        broker.send_overseas_order = AsyncMock(
+            return_value={"rt_cd": "1", "msg1": "모의투자 주문가능금액이 부족합니다."}
+        )
+        return broker
+
+    def _make_buy_match_overseas(self, stock_code: str = "MLECW") -> ScenarioMatch:
+        return ScenarioMatch(
+            stock_code=stock_code,
+            matched_scenario=None,
+            action=ScenarioAction.BUY,
+            confidence=85,
+            rationale="Test buy",
+        )
+
+    @pytest.mark.asyncio
+    async def test_cooldown_set_on_insufficient_balance(
+        self, mock_broker: MagicMock, mock_overseas_broker: MagicMock,
+        mock_overseas_market: MagicMock,
+    ) -> None:
+        """BUY cooldown entry is created after 주문가능금액 rejection."""
+        engine = MagicMock(spec=ScenarioEngine)
+        engine.evaluate = MagicMock(return_value=self._make_buy_match_overseas("MLECW"))
+        buy_cooldown: dict[str, float] = {}
+
+        with patch("src.main.log_trade"):
+            await trading_cycle(
+                broker=mock_broker,
+                overseas_broker=mock_overseas_broker,
+                scenario_engine=engine,
+                playbook=_make_playbook("US_NASDAQ"),
+                risk=MagicMock(),
+                db_conn=MagicMock(),
+                decision_logger=MagicMock(),
+                context_store=MagicMock(get_latest_timeframe=MagicMock(return_value=None)),
+                criticality_assessor=MagicMock(
+                    assess_market_conditions=MagicMock(return_value=MagicMock(value="NORMAL")),
+                    get_timeout=MagicMock(return_value=5.0),
+                ),
+                telegram=MagicMock(
+                    notify_trade_execution=AsyncMock(),
+                    notify_fat_finger=AsyncMock(),
+                    notify_circuit_breaker=AsyncMock(),
+                    notify_scenario_matched=AsyncMock(),
+                ),
+                market=mock_overseas_market,
+                stock_code="MLECW",
+                scan_candidates={},
+                buy_cooldown=buy_cooldown,
+            )
+
+        assert "US_NASDAQ:MLECW" in buy_cooldown
+        assert buy_cooldown["US_NASDAQ:MLECW"] > 0
+
+    @pytest.mark.asyncio
+    async def test_cooldown_skips_buy(
+        self, mock_broker: MagicMock, mock_overseas_broker: MagicMock,
+        mock_overseas_market: MagicMock,
+    ) -> None:
+        """BUY is skipped when cooldown is active for the stock."""
+        engine = MagicMock(spec=ScenarioEngine)
+        engine.evaluate = MagicMock(return_value=self._make_buy_match_overseas("MLECW"))
+
+        import asyncio
+        # Set an active cooldown (expires far in the future)
+        buy_cooldown: dict[str, float] = {
+            "US_NASDAQ:MLECW": asyncio.get_event_loop().time() + 600
+        }
+
+        with patch("src.main.log_trade"):
+            await trading_cycle(
+                broker=mock_broker,
+                overseas_broker=mock_overseas_broker,
+                scenario_engine=engine,
+                playbook=_make_playbook("US_NASDAQ"),
+                risk=MagicMock(),
+                db_conn=MagicMock(),
+                decision_logger=MagicMock(),
+                context_store=MagicMock(get_latest_timeframe=MagicMock(return_value=None)),
+                criticality_assessor=MagicMock(
+                    assess_market_conditions=MagicMock(return_value=MagicMock(value="NORMAL")),
+                    get_timeout=MagicMock(return_value=5.0),
+                ),
+                telegram=MagicMock(
+                    notify_trade_execution=AsyncMock(),
+                    notify_fat_finger=AsyncMock(),
+                    notify_circuit_breaker=AsyncMock(),
+                    notify_scenario_matched=AsyncMock(),
+                ),
+                market=mock_overseas_market,
+                stock_code="MLECW",
+                scan_candidates={},
+                buy_cooldown=buy_cooldown,
+            )
+
+        # Order should NOT have been sent
+        mock_overseas_broker.send_overseas_order.assert_not_called()
+
+    @pytest.mark.asyncio
+    async def test_cooldown_not_set_on_other_errors(
+        self, mock_broker: MagicMock, mock_overseas_market: MagicMock,
+    ) -> None:
+        """Cooldown is NOT set for non-balance-related rejections."""
+        engine = MagicMock(spec=ScenarioEngine)
+        engine.evaluate = MagicMock(return_value=self._make_buy_match_overseas("MLECW"))
+        # Different rejection reason
+        overseas_broker = MagicMock()
+        overseas_broker.get_overseas_price = AsyncMock(
+            return_value={"output": {"last": "1.0", "rate": "0.0",
+                                     "high": "1.05", "low": "0.95", "tvol": "1000000"}}
+        )
+        overseas_broker.get_overseas_balance = AsyncMock(return_value={
+            "output1": [],
+            "output2": [{"frcr_dncl_amt_2": "50000", "frcr_evlu_tota": "50000",
+                         "frcr_buy_amt_smtl": "0"}],
+        })
+        overseas_broker.send_overseas_order = AsyncMock(
+            return_value={"rt_cd": "1", "msg1": "기타 오류 메시지"}
+        )
+        buy_cooldown: dict[str, float] = {}
+
+        with patch("src.main.log_trade"):
+            await trading_cycle(
+                broker=mock_broker,
+                overseas_broker=overseas_broker,
+                scenario_engine=engine,
+                playbook=_make_playbook("US_NASDAQ"),
+                risk=MagicMock(),
+                db_conn=MagicMock(),
+                decision_logger=MagicMock(),
+                context_store=MagicMock(get_latest_timeframe=MagicMock(return_value=None)),
+                criticality_assessor=MagicMock(
+                    assess_market_conditions=MagicMock(return_value=MagicMock(value="NORMAL")),
+                    get_timeout=MagicMock(return_value=5.0),
+                ),
+                telegram=MagicMock(
+                    notify_trade_execution=AsyncMock(),
+                    notify_fat_finger=AsyncMock(),
+                    notify_circuit_breaker=AsyncMock(),
+                    notify_scenario_matched=AsyncMock(),
+                ),
+                market=mock_overseas_market,
+                stock_code="MLECW",
+                scan_candidates={},
+                buy_cooldown=buy_cooldown,
+            )
+
+        # Cooldown should NOT be set for non-balance errors
+        assert "US_NASDAQ:MLECW" not in buy_cooldown
+
+    @pytest.mark.asyncio
+    async def test_no_cooldown_param_still_works(
+        self, mock_broker: MagicMock, mock_overseas_broker: MagicMock,
+        mock_overseas_market: MagicMock,
+    ) -> None:
+        """trading_cycle works normally when buy_cooldown is None (default)."""
+        engine = MagicMock(spec=ScenarioEngine)
+        engine.evaluate = MagicMock(return_value=self._make_buy_match_overseas("MLECW"))
+
+        with patch("src.main.log_trade"):
+            await trading_cycle(
+                broker=mock_broker,
+                overseas_broker=mock_overseas_broker,
+                scenario_engine=engine,
+                playbook=_make_playbook("US_NASDAQ"),
+                risk=MagicMock(),
+                db_conn=MagicMock(),
+                decision_logger=MagicMock(),
+                context_store=MagicMock(get_latest_timeframe=MagicMock(return_value=None)),
+                criticality_assessor=MagicMock(
+                    assess_market_conditions=MagicMock(return_value=MagicMock(value="NORMAL")),
+                    get_timeout=MagicMock(return_value=5.0),
+                ),
+                telegram=MagicMock(
+                    notify_trade_execution=AsyncMock(),
+                    notify_fat_finger=AsyncMock(),
+                    notify_circuit_breaker=AsyncMock(),
+                    notify_scenario_matched=AsyncMock(),
+                ),
+                market=mock_overseas_market,
+                stock_code="MLECW",
+                scan_candidates={},
+                # buy_cooldown not passed → defaults to None
+            )
+
+        # Should attempt the order (and fail), but not crash
+        mock_overseas_broker.send_overseas_order.assert_called_once()
+
+
 # ---------------------------------------------------------------------------
 # market_outlook BUY confidence threshold tests (#173)
 # ---------------------------------------------------------------------------
@@ -2496,3 +2848,156 @@ class TestMarketOutlookConfidenceThreshold:
         call_args = decision_logger.log_decision.call_args
         assert call_args is not None
         assert call_args.kwargs["action"] == "BUY"
+
+
+@pytest.mark.asyncio
+async def test_buy_suppressed_when_open_position_exists() -> None:
+    """BUY should be suppressed when an open position already exists for the stock."""
+    db_conn = init_db(":memory:")
+    decision_logger = DecisionLogger(db_conn)
+
+    # 기존 BUY 포지션 DB에 기록 (중복 매수 상황)
+    buy_decision_id = decision_logger.log_decision(
+        stock_code="NP",
+        market="US",
+        exchange_code="AMS",
+        action="BUY",
+        confidence=90,
+        rationale="initial entry",
+        context_snapshot={},
+        input_data={},
+    )
+    log_trade(
+        conn=db_conn,
+        stock_code="NP",
+        action="BUY",
+        confidence=90,
+        rationale="initial entry",
+        quantity=10,
+        price=50.0,
+        market="US",
+        exchange_code="AMS",
+        decision_id=buy_decision_id,
+    )
+
+    broker = MagicMock()
+    broker.send_order = AsyncMock(return_value={"msg1": "OK"})
+
+    overseas_broker = MagicMock()
+    overseas_broker.get_overseas_price = AsyncMock(
+        return_value={"output": {"last": "51.0", "rate": "2.0", "high": "52.0", "low": "50.0", "tvol": "1000000"}}
+    )
+    overseas_broker.get_overseas_balance = AsyncMock(
+        return_value={
+            "output1": [],
+            "output2": [{"frcr_dncl_amt_2": "10000", "frcr_evlu_tota": "10000", "frcr_buy_amt_smtl": "0"}],
+        }
+    )
+    overseas_broker.send_overseas_order = AsyncMock(return_value={"msg1": "OK"})
+
+    engine = MagicMock(spec=ScenarioEngine)
+    engine.evaluate = MagicMock(return_value=_make_buy_match(stock_code="NP"))
+
+    market = MagicMock()
+    market.name = "United States"
+    market.code = "US"
+    market.exchange_code = "AMS"
+    market.is_domestic = False
+
+    telegram = MagicMock()
+    telegram.notify_trade_execution = AsyncMock()
+    telegram.notify_fat_finger = AsyncMock()
+    telegram.notify_circuit_breaker = AsyncMock()
+    telegram.notify_scenario_matched = AsyncMock()
+
+    await trading_cycle(
+        broker=broker,
+        overseas_broker=overseas_broker,
+        scenario_engine=engine,
+        playbook=_make_playbook(market="US"),
+        risk=MagicMock(),
+        db_conn=db_conn,
+        decision_logger=decision_logger,
+        context_store=MagicMock(
+            get_latest_timeframe=MagicMock(return_value=None),
+            set_context=MagicMock(),
+        ),
+        criticality_assessor=MagicMock(
+            assess_market_conditions=MagicMock(return_value=MagicMock(value="NORMAL")),
+            get_timeout=MagicMock(return_value=5.0),
+        ),
+        telegram=telegram,
+        market=market,
+        stock_code="NP",
+        scan_candidates={},
+    )
+
+    # 이미 보유 중이므로 주문이 실행되지 않아야 함
+    broker.send_order.assert_not_called()
+    overseas_broker.send_overseas_order.assert_not_called()
+
+
+@pytest.mark.asyncio
+async def test_buy_proceeds_when_no_open_position() -> None:
+    """BUY should proceed normally when no open position exists for the stock."""
+    db_conn = init_db(":memory:")
+    decision_logger = DecisionLogger(db_conn)
+    # DB가 비어있는 상태 — 기존 포지션 없음
+
+    broker = MagicMock()
+    broker.send_order = AsyncMock(return_value={"msg1": "OK"})
+
+    overseas_broker = MagicMock()
+    overseas_broker.get_overseas_price = AsyncMock(
+        return_value={"output": {"last": "100.0", "rate": "1.0", "high": "101.0", "low": "99.0", "tvol": "500000"}}
+    )
+    overseas_broker.get_overseas_balance = AsyncMock(
+        return_value={
+            "output1": [],
+            "output2": [{"frcr_dncl_amt_2": "50000", "frcr_evlu_tota": "50000", "frcr_buy_amt_smtl": "0"}],
+        }
+    )
+    overseas_broker.send_overseas_order = AsyncMock(return_value={"msg1": "OK"})
+
+    engine = MagicMock(spec=ScenarioEngine)
+    engine.evaluate = MagicMock(return_value=_make_buy_match(stock_code="KNRX"))
+
+    market = MagicMock()
+    market.name = "United States"
+    market.code = "US"
+    market.exchange_code = "NAS"
+    market.is_domestic = False
+
+    risk = MagicMock()
+    risk.validate_order = MagicMock()
+
+    telegram = MagicMock()
+    telegram.notify_trade_execution = AsyncMock()
+    telegram.notify_fat_finger = AsyncMock()
+    telegram.notify_circuit_breaker = AsyncMock()
+    telegram.notify_scenario_matched = AsyncMock()
+
+    await trading_cycle(
+        broker=broker,
+        overseas_broker=overseas_broker,
+        scenario_engine=engine,
+        playbook=_make_playbook(market="US"),
+        risk=risk,
+        db_conn=db_conn,
+        decision_logger=decision_logger,
+        context_store=MagicMock(
+            get_latest_timeframe=MagicMock(return_value=None),
+            set_context=MagicMock(),
+        ),
+        criticality_assessor=MagicMock(
+            assess_market_conditions=MagicMock(return_value=MagicMock(value="NORMAL")),
+            get_timeout=MagicMock(return_value=5.0),
+        ),
+        telegram=telegram,
+        market=market,
+        stock_code="KNRX",
+        scan_candidates={},
+    )
+
+    # 포지션이 없으므로 해외 주문이 실행되어야 함
+    overseas_broker.send_overseas_order.assert_called_once()

tests/test_overseas_broker.py

@@ -414,7 +414,7 @@ class TestSendOverseasOrder:
 
     @pytest.mark.asyncio
     async def test_sell_limit_order(self, overseas_broker: OverseasBroker) -> None:
-        """Limit sell order should use VTTT1006U and ORD_DVSN=00."""
+        """Limit sell order should use VTTT1001U and ORD_DVSN=00."""
         mock_resp = AsyncMock()
         mock_resp.status = 200
         mock_resp.json = AsyncMock(return_value={"rt_cd": "0"})
@@ -428,7 +428,7 @@ class TestSendOverseasOrder:
         result = await overseas_broker.send_overseas_order("NYSE", "MSFT", "SELL", 5, price=350.0)
         assert result["rt_cd"] == "0"
 
-        overseas_broker._broker._auth_headers.assert_called_with("VTTT1006U")
+        overseas_broker._broker._auth_headers.assert_called_with("VTTT1001U")
 
         call_args = mock_session.post.call_args
         body = call_args[1]["json"]

tests/test_smart_scanner.py

@@ -350,6 +350,42 @@ class TestSmartVolatilityScanner:
         assert [c.stock_code for c in candidates] == ["ABCD"]
 
 
+class TestImpliedRSIFormula:
+    """Test the implied_rsi formula in SmartVolatilityScanner (issue #181)."""
+
+    def test_neutral_change_gives_neutral_rsi(self) -> None:
+        """0% change → implied_rsi = 50 (neutral)."""
+        # formula: 50 + (change_rate * 2.0)
+        rsi = max(0.0, min(100.0, 50.0 + (0.0 * 2.0)))
+        assert rsi == 50.0
+
+    def test_10pct_change_gives_rsi_70(self) -> None:
+        """10% upward change → implied_rsi = 70 (momentum signal)."""
+        rsi = max(0.0, min(100.0, 50.0 + (10.0 * 2.0)))
+        assert rsi == 70.0
+
+    def test_minus_10pct_gives_rsi_30(self) -> None:
+        """-10% change → implied_rsi = 30 (oversold signal)."""
+        rsi = max(0.0, min(100.0, 50.0 + (-10.0 * 2.0)))
+        assert rsi == 30.0
+
+    def test_saturation_at_25pct(self) -> None:
+        """Saturation occurs at >=25% change (not 12.5% as with old coefficient 4.0)."""
+        rsi_12pct = max(0.0, min(100.0, 50.0 + (12.5 * 2.0)))
+        rsi_25pct = max(0.0, min(100.0, 50.0 + (25.0 * 2.0)))
+        rsi_30pct = max(0.0, min(100.0, 50.0 + (30.0 * 2.0)))
+        # At 12.5% change: RSI = 75 (not 100, unlike old formula)
+        assert rsi_12pct == 75.0
+        # At 25%+ saturation
+        assert rsi_25pct == 100.0
+        assert rsi_30pct == 100.0  # Capped
+
+    def test_negative_saturation(self) -> None:
+        """Saturation at -25% gives RSI = 0."""
+        rsi = max(0.0, min(100.0, 50.0 + (-25.0 * 2.0)))
+        assert rsi == 0.0
+
+
 class TestRSICalculation:
     """Test RSI calculation in VolatilityAnalyzer."""
 

tests/test_telegram_commands.py

@@ -876,6 +876,54 @@ class TestGetUpdates:
 
             assert updates == []
 
+    @pytest.mark.asyncio
+    async def test_get_updates_409_stops_polling(self) -> None:
+        """409 Conflict response stops the poller (_running = False) and returns empty list."""
+        client = TelegramClient(bot_token="123:abc", chat_id="456", enabled=True)
+        handler = TelegramCommandHandler(client)
+        handler._running = True  # simulate active poller
+
+        mock_resp = AsyncMock()
+        mock_resp.status = 409
+        mock_resp.text = AsyncMock(
+            return_value='{"ok":false,"error_code":409,"description":"Conflict"}'
+        )
+        mock_resp.__aenter__ = AsyncMock(return_value=mock_resp)
+        mock_resp.__aexit__ = AsyncMock(return_value=False)
+
+        with patch("aiohttp.ClientSession.post", return_value=mock_resp):
+            updates = await handler._get_updates()
+
+        assert updates == []
+        assert handler._running is False  # poller stopped
+
+    @pytest.mark.asyncio
+    async def test_poll_loop_exits_after_409(self) -> None:
+        """_poll_loop exits naturally after _running is set to False by a 409 response."""
+        import asyncio as _asyncio
+
+        client = TelegramClient(bot_token="123:abc", chat_id="456", enabled=True)
+        handler = TelegramCommandHandler(client)
+
+        call_count = 0
+
+        async def mock_get_updates_409() -> list[dict]:
+            nonlocal call_count
+            call_count += 1
+            # Simulate 409 stopping the poller
+            handler._running = False
+            return []
+
+        handler._get_updates = mock_get_updates_409  # type: ignore[method-assign]
+
+        handler._running = True
+        task = _asyncio.create_task(handler._poll_loop())
+        await _asyncio.wait_for(task, timeout=2.0)
+
+        # _get_updates called exactly once, then loop exited
+        assert call_count == 1
+        assert handler._running is False
+
 
 class TestCommandWithArgs:
     """Test register_command_with_args and argument dispatch."""