Skip to main content
hc
Submit
mcpSource-backedReview first Safety ✓ Privacy ✓

FastAPI-MCP Server

FastAPI-native package that exposes FastAPI endpoints as Model Context Protocol tools while preserving schemas, docs, and existing authentication dependencies.

by Tadata·added 2026-06-05·
Claude CodeClaude Desktop
HarnessClaude CodeClaude Desktop
Review first — review before installing

Open the source and read safety notes before installing.

Safety notes

  • FastAPI-MCP can expose real API operations as tools; do not blindly expose admin, destructive, payment, credential, or production-write endpoints.
  • Preserve and test FastAPI authentication dependencies before letting agents call protected tools.
  • Review request models, side effects, rate limits, and authorization boundaries for each endpoint.
  • Prefer explicit allowlists and non-production deployments for early MCP testing.

Privacy notes

  • Request schemas, response schemas, OpenAPI docs, route names, validation errors, and endpoint outputs may be visible to the MCP client and model.
  • Endpoint calls can expose user data, internal identifiers, tokens in payloads, and business logic.
  • Keep API credentials, service secrets, and test-user tokens out of prompts, repository files, and logs.

Prerequisites

  • Python 3.10 or newer, with Python 3.12 recommended by the project.
  • Existing FastAPI application or a reviewed FastAPI service design.
  • uv or pip for installing fastapi-mcp.
  • Clear endpoint allowlist and authentication policy before exposing API operations to an agent.
  • MCP client that can connect to the mounted or separately deployed MCP endpoint.

Schema details

Install type
cli
Troubleshooting
No
Source repository stats
Scope
Source repo
Collection metadata
Estimated setup
15 minutes
Difficulty
intermediate
Full copyable content
from fastapi import FastAPI
from fastapi_mcp import FastApiMCP

app = FastAPI()

mcp = FastApiMCP(app)
mcp.mount()

About this resource

Content

FastAPI-MCP is a FastAPI-native package for exposing FastAPI endpoints as MCP tools. It preserves request and response schemas, endpoint documentation, and FastAPI dependency-based authentication patterns instead of treating an API only as a generic OpenAPI document.

The simplest documented pattern mounts an MCP server directly into a FastAPI app so the MCP endpoint becomes available from the application.

Source Review

These sources were reviewed on 2026-06-05. Prefer live documentation for current installation, mounting, deployment, authentication, and endpoint selection options.

Features

  • Expose FastAPI endpoints as MCP tools.
  • Preserve request models, response models, and route documentation.
  • Use existing FastAPI dependencies for authentication and authorization.
  • Mount the MCP server into the same app or deploy it separately.
  • Use ASGI transport directly with the FastAPI app.
  • Add MCP support with minimal code for existing services.

Installation

Install with uv:

uv add fastapi-mcp

Or install with pip:

pip install fastapi-mcp

Basic FastAPI integration:

from fastapi import FastAPI
from fastapi_mcp import FastApiMCP

app = FastAPI()

mcp = FastApiMCP(app)
mcp.mount()

The generated MCP endpoint is available from the mounted application path documented by the package.

Use Cases

  • Give an internal agent controlled access to selected FastAPI operations.
  • Add MCP tooling to a FastAPI backend without writing a custom MCP server.
  • Preserve existing Pydantic schema descriptions as tool context.
  • Reuse FastAPI authentication dependencies for protected MCP tools.
  • Test an API as agent-callable tools in staging before production rollout.

Safety and Privacy

Treat FastAPI-MCP as a way to expose live API capabilities, not just docs. Review which endpoints become tools, preserve authentication, and block destructive or sensitive operations unless they are explicitly intended for agent use.

Endpoint schemas, payloads, validation errors, and responses may reveal internal data models or user data. Use redacted test data and non-production environments when experimenting.

Duplicate Check

Existing entries include generic OpenAPI and API tooling, but no tadata-org/fastapi_mcp entry was found in content/mcp. This entry is for the FastAPI-native MCP package and belongs in content/mcp.

#fastapi#python#api#auth#server-framework

Source citations

Signals

Loading live community signals…

More like this, weekly

A short, calm digest of reviewed Claude resources. Unsubscribe any time.