Debug-MCP

Instructions

Implementation Reference

• src/mcp_debug_tool/server.py:611-665 (handler)

  The primary handler function for the 'sessions_step_over' MCP tool. It validates the sessionId from arguments, calls SessionManager.step_over_async, serializes the response, and handles errors appropriately.
  async def _handle_sessions_step_over(self, arguments: dict) -> list[TextContent]: """ Handler for sessions_step_over tool. Steps over the current line. """ try: session_id = arguments.get("sessionId") if not session_id: return [ TextContent( type="text", text=json.dumps({ "error": { "type": "ValueError", "message": "sessionId is required", } }), ) ] response = await self.session_manager.step_over_async(session_id) result = response.model_dump() return [ TextContent( type="text", text=json.dumps(result), ) ] except KeyError as e: return [ TextContent( type="text", text=json.dumps({ "error": { "type": "SessionNotFound", "message": str(e), } }), ) ] except Exception as e: logger.exception("Error in step_over") return [ TextContent( type="text", text=json.dumps({ "error": { "type": type(e).__name__, "message": str(e), } }), ) ]
• src/mcp_debug_tool/server.py:176-189 (registration)

  Registration of the 'sessions_step_over' tool in the list_tools() function, including name, description, and input schema requiring 'sessionId'.
  Tool( name="sessions_step_over", description="Step over the current line (requires active breakpoint)", inputSchema={ "type": "object", "properties": { "sessionId": { "type": "string", "description": "The debug session ID", }, }, "required": ["sessionId"], }, ),
• src/mcp_debug_tool/server.py:176-189 (schema)

  Input schema definition for the 'sessions_step_over' tool, specifying required 'sessionId' parameter.
  Tool( name="sessions_step_over", description="Step over the current line (requires active breakpoint)", inputSchema={ "type": "object", "properties": { "sessionId": { "type": "string", "description": "The debug session ID", }, }, "required": ["sessionId"], }, ),
• src/mcp_debug_tool/sessions.py:982-988 (helper)

  Async wrapper in SessionManager that delegates to synchronous step_over method.
  async def step_over_async(self, session_id: str) -> BreakpointResponse: """ Async wrapper for step_over. Runs the synchronous step_over in a thread pool to avoid blocking. """ return await asyncio.to_thread(self.step_over, session_id)