fix: enable cross-job portfolio continuity in get_previous_trading_day

Remove job_id filter from get_previous_trading_day() SQL query to enable
portfolio continuity across jobs. Previously, new jobs would reset to
initial $10,000 cash instead of continuing from previous job's ending
position.

Root cause: get_previous_trading_day() filtered by job_id, while
get_current_position_from_db() correctly queries across all jobs.
This inconsistency caused starting_cash to default to initial_cash
when no previous day was found within the same job.

Changes:
- api/database.py: Remove job_id filter from SQL WHERE clause
- tests/unit/test_database_helpers.py: Add test for cross-job continuity

Fixes position tracking bug where subsequent jobs on consecutive dates
would not recognize previous day's holdings from different job.

CHANGELOG.md

@@ -7,6 +7,21 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.4.2] - 2025-11-07
+
+### Fixed
+- **Critical:** Fixed negative cash position bug where trades calculated from initial capital instead of accumulating
+  - Root cause: MCP tools return `CallToolResult` objects with position data in `structuredContent` field, but `ContextInjector` was checking `isinstance(result, dict)` which always failed
+  - Impact: Each trade checked cash against initial $10,000 instead of cumulative position, allowing over-spending and resulting in negative cash balances (e.g., -$8,768.68 after 11 trades totaling $18,768.68)
+  - Solution: Updated `ContextInjector` to extract position dict from `CallToolResult.structuredContent` before validation
+  - Fix ensures proper intra-day position tracking with cumulative cash checks preventing over-trading
+  - Updated unit tests to mock `CallToolResult` objects matching production MCP behavior
+  - Locations: `agent/context_injector.py:95-109`, `tests/unit/test_context_injector.py:26-53`
+- Enabled MCP service logging by redirecting stdout/stderr from `/dev/null` to main process for better debugging
+  - Previously, all MCP tool debug output was silently discarded
+  - Now visible in docker logs for diagnosing parameter injection and trade execution issues
+  - Location: `agent_tools/start_mcp_services.py:81-88`
+
 ### Fixed
 - **Critical:** Fixed stale jobs blocking new jobs after Docker container restart
   - Root cause: Jobs with status 'pending', 'downloading_data', or 'running' remained in database after container shutdown, preventing new job creation

agent/context_injector.py

@@ -88,9 +88,17 @@ class ContextInjector:
 
         # Update position state after successful trade
         if request.name in ["buy", "sell"]:
-            # Check if result is a valid position dict (not an error)
-            if isinstance(result, dict) and "error" not in result and "CASH" in result:
+            # Extract position dict from MCP result
+            # MCP tools return CallToolResult objects with structuredContent field
+            position_dict = None
+            if hasattr(result, 'structuredContent') and result.structuredContent:
+                position_dict = result.structuredContent
+            elif isinstance(result, dict):
+                position_dict = result
+
+            # Check if position dict is valid (not an error) and update state
+            if position_dict and "error" not in position_dict and "CASH" in position_dict:
                 # Update our tracked position with the new state
-                self._current_position = result.copy()
+                self._current_position = position_dict.copy()
 
         return result

agent_tools/start_mcp_services.py

@@ -78,10 +78,11 @@ class MCPServiceManager:
             env['PYTHONPATH'] = str(Path.cwd())
 
             # Start service process (output goes to Docker logs)
+            # Enable stdout/stderr for debugging (previously sent to DEVNULL)
             process = subprocess.Popen(
                 [sys.executable, str(script_path)],
-                stdout=subprocess.DEVNULL,
-                stderr=subprocess.DEVNULL,
+                stdout=sys.stdout,  # Redirect to main process stdout
+                stderr=sys.stderr,  # Redirect to main process stderr
                 cwd=Path.cwd(),  # Use current working directory (/app)
                 env=env  # Pass environment with PYTHONPATH
             )

api/database.py

@@ -611,6 +611,10 @@ class Database:
 
         Handles weekends/holidays by finding actual previous trading day.
 
+        NOTE: Queries across ALL jobs for the given model to enable portfolio
+        continuity even when new jobs are created with overlapping date ranges.
+        The job_id parameter is kept for API compatibility but not used in the query.
+
         Returns:
             dict with keys: id, date, ending_cash, ending_portfolio_value
             or None if no previous day exists
@@ -619,11 +623,11 @@ class Database:
             """
             SELECT id, date, ending_cash, ending_portfolio_value
             FROM trading_days
-            WHERE job_id = ? AND model = ? AND date < ?
+            WHERE model = ? AND date < ?
             ORDER BY date DESC
             LIMIT 1
             """,
-            (job_id, model, current_date)
+            (model, current_date)
         )
 
         row = cursor.fetchone()

tests/unit/test_context_injector.py

@@ -2,6 +2,7 @@
 
 import pytest
 from agent.context_injector import ContextInjector
+from unittest.mock import Mock
 
 
 @pytest.fixture
@@ -22,27 +23,34 @@ class MockRequest:
         self.args = args or {}
 
 
+def create_mcp_result(position_dict):
+    """Create a mock MCP CallToolResult object matching production behavior."""
+    result = Mock()
+    result.structuredContent = position_dict
+    return result
+
+
 async def mock_handler_success(request):
-    """Mock handler that returns a successful position update."""
+    """Mock handler that returns a successful position update as MCP CallToolResult."""
     # Simulate a successful trade returning updated position
     if request.name == "sell":
-        return {
+        return create_mcp_result({
             "CASH": 1100.0,
             "AAPL": 7,
             "MSFT": 5
-        }
+        })
     elif request.name == "buy":
-        return {
+        return create_mcp_result({
             "CASH": 50.0,
             "AAPL": 7,
             "MSFT": 12
-        }
-    return {}
+        })
+    return create_mcp_result({})
 
 
 async def mock_handler_error(request):
-    """Mock handler that returns an error."""
-    return {"error": "Insufficient cash"}
+    """Mock handler that returns an error as MCP CallToolResult."""
+    return create_mcp_result({"error": "Insufficient cash"})
 
 
 @pytest.mark.asyncio
@@ -68,17 +76,17 @@ async def test_context_injector_injects_parameters(injector):
     """Test that context parameters are injected into buy/sell requests."""
     request = MockRequest("buy", {"symbol": "AAPL", "amount": 10})
 
-    # Mock handler that just returns the request args
+    # Mock handler that returns MCP result containing the request args
     async def handler(req):
-        return req.args
+        return create_mcp_result(req.args)
 
     result = await injector(request, handler)
 
-    # Verify context was injected
-    assert result["signature"] == "test-model"
-    assert result["today_date"] == "2025-01-15"
-    assert result["job_id"] == "test-job-123"
-    assert result["trading_day_id"] == 1
+    # Verify context was injected (result is MCP CallToolResult object)
+    assert result.structuredContent["signature"] == "test-model"
+    assert result.structuredContent["today_date"] == "2025-01-15"
+    assert result.structuredContent["job_id"] == "test-job-123"
+    assert result.structuredContent["trading_day_id"] == 1
 
 
 @pytest.mark.asyncio
@@ -132,7 +140,7 @@ async def test_context_injector_does_not_update_position_on_error(injector):
 
     # Verify position was NOT updated
     assert injector._current_position == original_position
-    assert "error" in result
+    assert "error" in result.structuredContent
 
 
 @pytest.mark.asyncio
@@ -146,7 +154,7 @@ async def test_context_injector_does_not_inject_position_for_non_trade_tools(inj
 
     async def verify_no_injection_handler(req):
         assert "_current_position" not in req.args
-        return {"results": []}
+        return create_mcp_result({"results": []})
 
     await injector(request, verify_no_injection_handler)
 
@@ -164,7 +172,7 @@ async def test_context_injector_full_trading_session_simulation(injector):
     async def handler1(req):
         # First trade should NOT have injected position
         assert req.args.get("_current_position") is None
-        return {"CASH": 1100.0, "AAPL": 7}
+        return create_mcp_result({"CASH": 1100.0, "AAPL": 7})
 
     result1 = await injector(request1, handler1)
     assert injector._current_position == {"CASH": 1100.0, "AAPL": 7}
@@ -176,7 +184,7 @@ async def test_context_injector_full_trading_session_simulation(injector):
         # Second trade SHOULD have injected position from trade 1
         assert req.args["_current_position"]["CASH"] == 1100.0
         assert req.args["_current_position"]["AAPL"] == 7
-        return {"CASH": 50.0, "AAPL": 7, "MSFT": 7}
+        return create_mcp_result({"CASH": 50.0, "AAPL": 7, "MSFT": 7})
 
     result2 = await injector(request2, handler2)
     assert injector._current_position == {"CASH": 50.0, "AAPL": 7, "MSFT": 7}
@@ -185,7 +193,7 @@ async def test_context_injector_full_trading_session_simulation(injector):
     request3 = MockRequest("buy", {"symbol": "GOOGL", "amount": 100})
 
     async def handler3(req):
-        return {"error": "Insufficient cash", "cash_available": 50.0}
+        return create_mcp_result({"error": "Insufficient cash", "cash_available": 50.0})
 
     result3 = await injector(request3, handler3)
     # Position should remain unchanged after failed trade

tests/unit/test_database_helpers.py

@@ -130,6 +130,44 @@ class TestDatabaseHelpers:
         assert previous is not None
         assert previous["date"] == "2025-01-17"
 
+    def test_get_previous_trading_day_across_jobs(self, db):
+        """Test retrieving previous trading day from different job (cross-job continuity)."""
+        # Setup: Create two jobs
+        db.connection.execute(
+            "INSERT INTO jobs (job_id, status, config_path, date_range, models, created_at) VALUES (?, ?, ?, ?, ?, ?)",
+            ("job-1", "completed", "config.json", "2025-10-07,2025-10-07", "deepseek-chat-v3.1", "2025-11-07T00:00:00Z")
+        )
+        db.connection.execute(
+            "INSERT INTO jobs (job_id, status, config_path, date_range, models, created_at) VALUES (?, ?, ?, ?, ?, ?)",
+            ("job-2", "running", "config.json", "2025-10-08,2025-10-08", "deepseek-chat-v3.1", "2025-11-07T01:00:00Z")
+        )
+
+        # Day 1 in job-1
+        db.create_trading_day(
+            job_id="job-1",
+            model="deepseek-chat-v3.1",
+            date="2025-10-07",
+            starting_cash=10000.0,
+            starting_portfolio_value=10000.0,
+            daily_profit=214.58,
+            daily_return_pct=2.15,
+            ending_cash=123.59,
+            ending_portfolio_value=10214.58
+        )
+
+        # Test: Get previous day from job-2 on next date
+        # Should find job-1's record (cross-job continuity)
+        previous = db.get_previous_trading_day(
+            job_id="job-2",
+            model="deepseek-chat-v3.1",
+            current_date="2025-10-08"
+        )
+
+        assert previous is not None
+        assert previous["date"] == "2025-10-07"
+        assert previous["ending_cash"] == 123.59
+        assert previous["ending_portfolio_value"] == 10214.58
+
     def test_get_ending_holdings(self, db):
         """Test retrieving ending holdings for a trading day."""
         db.connection.execute(