PrefectHQ/fastmcp

What it solves

FastMCP simplifies the process of building applications using the Model Context Protocol (MCP), which connects Large Language Models (LLMs) to external tools and data. It removes the complexity of manually managing protocol lifecycles, transport negotiation, authentication, and schema generation, allowing developers to focus on the core logic of their tools.

How it works

FastMCP provides a full application framework for three main components:

• Servers: Converts standard Python functions into MCP-compliant tools, resources, and prompts, automatically generating the necessary documentation and validation schemas.
• Clients: Enables connection to any local or remote MCP server via URL, handling the underlying protocol support.
• Apps: Allows developers to create interactive user interfaces that are rendered directly within the LLM conversation.

Who it’s for

Python and TypeScript developers who want to integrate LLMs with custom tools and data sources using the Model Context Protocol.

Highlights

• Automatic Schema Generation: Automatically creates schemas, validation, and documentation from Python functions.
• Full Protocol Support: Manages transport negotiation and authentication for both clients and servers.
• Cros-Language Support: Available in both Python and TypeScript.
• Enterprise Scaling: Integrates with Prefect Horizon for centralized governance, RBAC, and observability.
• LLM-Friendly Docs: Provides documentation in llms.txt format for easy consumption by AI models.