About FastAPI-MCP
FastAPI-MCP exposes FastAPI endpoints as MCP tools and reuses the application's existing authentication dependencies. It targets Python developers who want to add MCP support to an existing FastAPI service, calling the app directly through ASGI.
Key features
- 01Authentication through existing FastAPI Depends()
- 02Preserved request and response model schemas
- 03Endpoint documentation kept as in Swagger
- 04Mountable in the same app or deployed separately
- 05Direct ASGI communication without extra HTTP calls
- 06Zero or minimal configuration required
Use cases
- 01Adding MCP tool access to an existing FastAPI service
- 02Applying existing authorization rules to MCP endpoints
- 03Offering internal APIs as MCP tools to clients such as Cursor or Claude
MCP support
FastAPI-MCP is an MCP server extension that converts FastAPI routes into MCP tools and mounts an MCP endpoint at /mcp for MCP clients to connect.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEFastAPI-MCP
Expose your FastAPI endpoints as Model Context Protocol (MCP) tools, with Auth!
Features
-
Authentication built in, using your existing FastAPI dependencies!
-
FastAPI-native: Not just another OpenAPI -> MCP converter
-
Zero/Minimal configuration required - just point it at your FastAPI app and it works
-
Preserving schemas of your request models and response models
-
Preserve documentation of all your endpoints, just as it is in Swagger
-
Flexible deployment - Mount your MCP server to the same app, or deploy separately
-
ASGI transport - Uses FastAPI's ASGI interface directly for efficient communication
Hosted Solution
If you prefer a managed hosted solution check out tadata.com.
Installation
We recommend using uv, a fast Python package installer:
uv add fastapi-mcp
Alternatively, you can install with pip:
pip install fastapi-mcp
Basic Usage
The simplest way to use FastAPI-MCP is to add an MCP server directly to your FastAPI application:
from fastapi import FastAPI
from fastapi_mcp import FastApiMCP
app = FastAPI()
mcp = FastApiMCP(app)
# Mount the MCP server directly to your FastAPI app
mcp.mount()
That's it! Your auto-generated MCP server is now available at https://app.base.url/mcp.
Documentation, Examples and Advanced Usage
FastAPI-MCP provides comprehensive documentation. Additionaly, check out the examples directory for code samples demonstrating these features in action.
FastAPI-first Approach
FastAPI-MCP is designed as a native extension of FastAPI, not just a converter that generates MCP tools from your API. This approach offers several key advantages:
-
Native dependencies: Secure your MCP endpoints using familiar FastAPI
Depends()for authentication and authorization -
ASGI transport: Communicates directly with your FastAPI app using its ASGI interface, eliminating the need for HTTP calls from the MCP to your API
-
Unified infrastructure: Your FastAPI app doesn't need to run separately from the MCP server (though separate deployment is also supported)
This design philosophy ensures minimum friction when adding MCP capabilities to your existing FastAPI services.
Development and Contributing
Thank you for considering contributing to FastAPI-MCP! We encourage the community to post Issues and create Pull Requests.
Before you get started, please see our Contribution Guide.
Community
Join MCParty Slack community to connect with other MCP enthusiasts, ask questions, and share your experiences with FastAPI-MCP.
Requirements
- Python 3.10+ (Recommended 3.12)
- uv
License
MIT License. Copyright (c) 2025 Tadata Inc.
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.