FastMCP is a TypeScript framework for building Model Context Protocol servers with tools, resources, prompts, and session-aware behavior. It sits on top of the official MCP SDK and adds higher-level conveniences for developers who want to expose application capabilities to AI clients without implementing the surrounding server infrastructure manually.

The framework includes HTTP streaming and SSE compatibility, HTTPS, custom routes, session and request tracking, CORS, prompt argument completion, in-memory testing, edge-runtime support, stateless deployment options, and a CLI for debugging. The README notes that this repository targets older handshake-based MCP revisions and does not implement the newer stateless 2026-07-28 specification.

FastMCP is useful for existing TypeScript MCP services built around those supported protocol revisions and for developers who value its ergonomic server abstractions. New projects targeting the latest MCP specification should pay attention to the compatibility warning and evaluate the successor direction referenced by the project.