MCP Test MCP

Instructions

Implementation Reference

• node-wrapper/python-src/src/mcp_test_mcp/tools/tools.py:19-141 (handler)

  The handler function for the 'list_tools' MCP tool. It is decorated with @mcp.tool for automatic registration. The function retrieves the list of tools from the connected target MCP server using client.list_tools(), processes them into a structured dictionary with input schemas, adds metadata, and handles connection and execution errors appropriately.
  @mcp.tool async def list_tools(ctx: Context) -> dict[str, Any]: """List all tools available on the connected MCP server. Retrieves comprehensive information about all tools exposed by the target server, including full input schemas to enable accurate tool invocation. Returns: Dictionary with tool listing including: - success: True on successful retrieval - tools: List of tool objects with name, description, and full input_schema - metadata: Total count, server info, timing information Raises: Returns error dict if not connected or retrieval fails """ start_time = time.perf_counter() try: # Verify connection exists client, state = ConnectionManager.require_connection() # User-facing progress update await ctx.info("Listing tools from connected MCP server") # Detailed technical log logger.info("Listing tools from connected MCP server") # Get tools from the server tools_result = await client.list_tools() elapsed_ms = (time.perf_counter() - start_time) * 1000 # Convert tools to dictionary format with full schemas # Note: client.list_tools() returns a list directly, not an object with .tools tools_list = [] for tool in tools_result: # inputSchema is already a dict, not a Pydantic model input_schema = tool.inputSchema if hasattr(tool, "inputSchema") and tool.inputSchema else {} tool_dict = { "name": tool.name, "description": tool.description if tool.description else "", "input_schema": input_schema, } tools_list.append(tool_dict) metadata = { "total_tools": len(tools_list), "server_url": state.server_url, "retrieved_at": time.time(), "request_time_ms": round(elapsed_ms, 2), } # Add server info if available if state.server_info: metadata["server_name"] = state.server_info.get("name", "unknown") metadata["server_version"] = state.server_info.get("version") # User-facing success update await ctx.info(f"Retrieved {len(tools_list)} tools from server") # Detailed technical log logger.info( f"Retrieved {len(tools_list)} tools from server", extra={ "tool_count": len(tools_list), "server_url": state.server_url, "duration_ms": elapsed_ms, }, ) return { "success": True, "tools": tools_list, "metadata": metadata, } except ConnectionError as e: elapsed_ms = (time.perf_counter() - start_time) * 1000 # User-facing error update await ctx.error(f"Not connected: {str(e)}") # Detailed technical log logger.error(f"Not connected: {str(e)}", extra={"duration_ms": elapsed_ms}) return { "success": False, "error": { "error_type": "not_connected", "message": str(e), "details": {}, "suggestion": "Use connect_to_server() to establish a connection first", }, "tools": [], "metadata": { "request_time_ms": round(elapsed_ms, 2), }, } except Exception as e: elapsed_ms = (time.perf_counter() - start_time) * 1000 # User-facing error update await ctx.error(f"Failed to list tools: {str(e)}") # Detailed technical log logger.exception("Failed to list tools", extra={"duration_ms": elapsed_ms}) # Increment error counter ConnectionManager.increment_stat("errors") return { "success": False, "error": { "error_type": "execution_error", "message": f"Failed to list tools: {str(e)}", "details": {"exception_type": type(e).__name__}, "suggestion": "Check that the server supports the tools capability and is responding correctly", }, "tools": [], "metadata": { "request_time_ms": round(elapsed_ms, 2), }, }
• node-wrapper/python-src/src/mcp_test_mcp/server.py:97-99 (registration)

  Import of the tools module in the main server.py file, which triggers the execution of the @mcp.tool decorators in tools/tools.py, thereby registering the list_tools tool with the FastMCP server instance.
  # This MUST happen after mcp instance is imported but before the server runs from .tools import connection, tools, resources, prompts, llm
• node-wrapper/python-src/src/mcp_test_mcp/tools/__init__.py:8-8 (registration)

  Re-export of the list_tools function from the tools submodule in the package __init__.py, making it available when importing from the tools package.
  from .tools import call_tool, list_tools