Why you'd want it
You declare a tool as a Python function and FastMCP generates the schema, validation and documentation; when you connect to a server by URL, it handles transport negotiation, authentication and the protocol lifecycle. Besides servers and clients it supports apps, which give tools interactive UIs rendered in the conversation. FastMCP 1.0 was incorporated into the official MCP Python SDK in 2024, and Prefect maintains a TypeScript counterpart.
Best for
- Python developers writing MCP servers
- Calling MCP servers from Python code
- Tools that need an interactive UI in chat
Use it when
You are writing an MCP server or client in Python and want schemas, transports and auth handled for you.
Skip it if
Your server is not written in Python; the TypeScript version lives in a separate repo, PrefectHQ/fastmcp-ts.
Editor's note
Moved from jlowin/fastmcp to PrefectHQ/fastmcp.