Question

You are building an MCP server with Python FastMCP so an AI agent can retrieve live interface statistics from your IOS-XE devices via RESTCONF. You have written a Python function get_interface_stats(device_ip: str, interface: str) that returns a dictionary of counters. You want the AI agent to be able to invoke this function as a callable capability, with FastMCP automatically generating the input schema from the function's type hints and docstring. Which FastMCP construct should you apply to the function?

Accepted Answer

Decorate the function with @mcp.tool() so FastMCP registers it as an invocable tool and derives the parameter schema from the type hints and docstring.

Answer

Decorate the function with @mcp.resource() so it is exposed as a read-only data endpoint the agent subscribes to.

Answer

Decorate the function with @mcp.prompt() so the agent receives it as a reusable prompt template.

Answer

Wrap the function in an @app.route() Flask decorator and let the agent call the HTTP endpoint directly.