feat(ai_client): Support external MCP tools and HITL approval

tests/test_external_mcp_e2e.py

@@ -0,0 +1,67 @@
+import asyncio
+import json
+import os
+from pathlib import Path
+import pytest
+from src.app_controller import AppController
+from src import mcp_client
+from src import ai_client
+from src import models
+
+@pytest.mark.asyncio
+async def test_external_mcp_e2e_refresh_and_call(tmp_path, monkeypatch):
+ # 1. Setup mock config and mock server script
+ config_file = tmp_path / "config.toml"
+ monkeypatch.setattr(models, "CONFIG_PATH", str(config_file))
+ 
+ mock_script = Path("scripts/mock_mcp_server.py").absolute()
+ 
+ mcp_config_file = tmp_path / "mcp_config.json"
+ mcp_data = {
+  "mcpServers": {
+   "e2e-server": {
+    "command": "python",
+    "args": [str(mock_script)],
+    "auto_start": True
+   }
+  }
+ }
+ mcp_config_file.write_text(json.dumps(mcp_data))
+ 
+ config_content = f"""
+[ai]
+mcp_config_path = "{mcp_config_file.as_posix()}"
+[projects]
+paths = []
+active = ""
+"""
+ config_file.write_text(config_content)
+ 
+ # 2. Initialize AppController
+ ctrl = AppController()
+ monkeypatch.setattr(ctrl, "_load_active_project", lambda: None)
+ ctrl.project = {}
+ 
+ # We need to mock start_services or just manually call what we need
+ ctrl.init_state()
+ 
+ # Trigger refresh event manually (since we don't have the background thread running in unit test)
+ await ctrl.refresh_external_mcps()
+ 
+ # 3. Verify tools are discovered
+ manager = mcp_client.get_external_mcp_manager()
+ tools = manager.get_all_tools()
+ assert "echo" in tools
+ 
+ # 4. Mock pre_tool_callback to auto-approve
+ mock_pre_tool = lambda desc, base, qa: "Approved"
+ 
+ # 5. Call execute_single_tool_call_async (via ai_client)
+ name, cid, out, orig = await ai_client._execute_single_tool_call_async(
+  "echo", {"message": "hello"}, "id1", ".", mock_pre_tool, None, 0
+ )
+ 
+ assert "ECHO: {'message': 'hello'}" in out
+ 
+ # Cleanup
+ await manager.stop_all()

tests/test_external_mcp_hitl.py

@@ -0,0 +1,62 @@
+import asyncio
+import json
+import pytest
+from unittest.mock import MagicMock, patch, AsyncMock
+from src import ai_client
+from src import mcp_client
+from src import models
+
+@pytest.mark.asyncio
+async def test_external_mcp_hitl_approval():
+    # 1. Setup mock manager and server
+    mock_manager = mcp_client.ExternalMCPManager()
+    mock_server = AsyncMock()
+    mock_server.name = "test-server"
+    mock_server.tools = {"ext_tool": {"name": "ext_tool", "description": "desc"}}
+    mock_server.call_tool.return_value = "Success"
+    mock_manager.servers["test-server"] = mock_server
+    
+    with patch("src.mcp_client.get_external_mcp_manager", return_value=mock_manager):
+        # 2. Setup ai_client callbacks
+        mock_pre_tool = MagicMock(return_value="Approved")
+        ai_client.confirm_and_run_callback = mock_pre_tool
+        
+        # 3. Call _execute_single_tool_call_async
+        name = "ext_tool"
+        args = {"arg1": "val1"}
+        call_id = "call_123"
+        base_dir = "."
+        
+        # We need to pass the callback to the function
+        name, cid, out, orig_name = await ai_client._execute_single_tool_call_async(
+            name, args, call_id, base_dir, mock_pre_tool, None, 0
+        )
+        
+        # 4. Assertions
+        assert out == "Success"
+        mock_pre_tool.assert_called_once()
+        # Check description contains EXTERNAL MCP
+        call_args = mock_pre_tool.call_args[0]
+        assert "EXTERNAL MCP TOOL: ext_tool" in call_args[0]
+        assert "arg1: 'val1'" in call_args[0]
+
+@pytest.mark.asyncio
+async def test_external_mcp_hitl_rejection():
+    mock_manager = mcp_client.ExternalMCPManager()
+    mock_server = AsyncMock()
+    mock_server.name = "test-server"
+    mock_server.tools = {"ext_tool": {"name": "ext_tool"}}
+    mock_manager.servers["test-server"] = mock_server
+    
+    with patch("src.mcp_client.get_external_mcp_manager", return_value=mock_manager):
+        mock_pre_tool = MagicMock(return_value=None) # Rejection
+        
+        name = "ext_tool"
+        args = {"arg1": "val1"}
+        
+        name, cid, out, orig_name = await ai_client._execute_single_tool_call_async(
+            name, args, "id", ".", mock_pre_tool, None, 0
+        )
+        
+        assert out == "USER REJECTED: tool execution cancelled"
+        mock_server.call_tool.assert_not_called()