What is FastMCP?
FastMCP is a framework for building Model Context Protocol servers, clients, and interactive applications. FastMCP serves developers who want to expose application logic through MCP without implementing the surrounding protocol machinery themselves. The framework provides a shared API while keeping application code in ordinary Python.
FastMCP is made by Prefect. The website describes an actively maintained standalone project and an official TypeScript counterpart built and maintained by the same team. FastMCP for TypeScript follows the same server, client, and app concepts, giving developers a related option when building in TypeScript.
What FastMCP can do
FastMCP covers servers, clients, and apps within the MCP application lifecycle. FastMCP servers expose application capabilities, clients connect to MCP endpoints, and apps add interactive interfaces to tool results. Across these components, the framework handles protocol responsibilities while application code defines the underlying behavior.
- FastMCP exposes Python functions as MCP tools.
- FastMCP publishes data and instructions as resources and prompts.
- FastMCP generates schemas and validates inputs and outputs.
- FastMCP connects clients to local or remote MCP servers.
- FastMCP returns forms, tables, charts, and other interactive interfaces.
- FastMCP manages transport, authentication, and protocol compatibility.
How FastMCP works
FastMCP starts with Python functions registered as tools through a decorator. FastMCP derives the function schema, validates inputs and outputs, and exposes the function through MCP. The example on the website creates a FastMCP instance, registers an addition function, and runs the server from the Python application.
FastMCP clients connect to a server URL while the framework handles protocol negotiation, authentication, and connection lifecycle. FastMCP supports connections through Python, the command line, or another MCP application. Interactive apps extend ordinary tool results with interfaces rendered directly in the conversation.
Who FastMCP is for
FastMCP is for developers building MCP-enabled applications and coding agents working with those developers. FastMCP supports projects that need callable Python functions, access to local or remote MCP servers, or interactive tool responses. The documentation is also designed for agents that need searchable reference material while working.
- FastMCP lets developers make Python application logic available as MCP tools.
- FastMCP lets client applications connect to local or remote MCP services.
- FastMCP lets tool builders return interactive forms, tables, and charts.
- FastMCP lets MCP-compatible agents search its documentation.
FastMCP strengths and limitations
FastMCP combines schema generation, validation, authentication, and protocol handling around application code. FastMCP also uses shared concepts across servers, clients, and apps. The website distinguishes this application-layer framework from Prefect Horizon, a separate enterprise MCP gateway for centralized deployment, discovery, access governance, and operational visibility.
- FastMCP documentation may include features that have not reached a stable release.
- FastMCP documentation reflects the project's main branch.
- FastMCP application-layer functionality is separate from the enterprise gateway capabilities described for Prefect Horizon.
Getting started with FastMCP
FastMCP can be added to a project with uv add fastmcp. FastMCP documentation directs developers to verify the package, find the appropriate upgrade guide, and follow a first-server walkthrough. That walkthrough covers creating a tool, running its server, calling the tool from a client, and adding an interactive interface.
FastMCP documentation is available as individual Markdown pages, an llms.txt page listing, and a complete llms-full.txt file. FastMCP also exposes documentation through https://gofastmcp.com/mcp for MCP-compatible agents. The website does not state package pricing and warns that the complete documentation file may exceed some context windows.
FastMCP FAQ
What is FastMCP?
FastMCP is a Python framework for building Model Context Protocol servers, clients, and interactive applications. FastMCP provides a shared API and manages schema generation, validation, transport, authentication, and protocol compatibility around application code.
What can you build with FastMCP?
FastMCP supports MCP servers that expose Python functions, data, and instructions as tools, resources, and prompts. FastMCP also supports clients for local or remote servers and interactive apps that return forms, tables, charts, and other interfaces in conversations.
How do you install FastMCP?
FastMCP can be added to a project with uv add fastmcp. FastMCP documentation then guides developers through package verification and a first-server workflow covering tool creation, server execution, client calls, and an interactive interface.
Can FastMCP connect to remote MCP servers?
FastMCP supports connections to local and remote MCP servers through Python, the command line, or another MCP application. FastMCP handles protocol negotiation, authentication, and connection lifecycle when a client connects to a server URL.
Does FastMCP support TypeScript?
FastMCP has an official TypeScript counterpart built and maintained by the same team. FastMCP for TypeScript follows the same concepts for servers, clients, and apps described in the Python framework documentation.
Can AI coding agents search FastMCP documentation?
FastMCP exposes its documentation through an MCP server at https://gofastmcp.com/mcp, allowing MCP-compatible agents to search documentation while working. FastMCP also provides Markdown pages, an llms.txt page listing, and a complete llms-full.txt documentation file.
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