FastMCP

Use it when

• Existing Python functions need to be exposed as MCP tools to Claude or another client without hand-writing JSON schemas, transport negotiation, or protocol lifecycle code
• A programmatic MCP client is needed to connect to and call any local or remote MCP server with full protocol support

What it solves

Not the fit when

• enterprise-scale MCP governance, SSO, and RBAC (Prefect Horizon is the paid product for that)
• non-Python stacks unless using the separate TypeScript counterpart
• hosting or deploying servers to production
• enterprise gateway governance and rbac
• browser automation
• model inference

Install

uv add fastmcp

Invoke

from fastmcp import FastMCP; mcp = FastMCP("Demo"); @mcp.tool decorator on a typed Python function; mcp.run() -- schema, validation, and docs are generated from the function signature

Alternatives

No reviewed alternatives recorded yet.