FastAPI-MCP

Automatically exposes existing FastAPI endpoints as MCP tools with zero/minimal configuration. Converts FastAPI routes into MCP-compatible tools while preserving schemas, documentation, and authentication, communicating via ASGI transport without HTTP overhead.

Evaluated Mar 06, 2026 (0d ago) v0.4.0

Homepage ↗ Repo ↗ Developer Tools fastapi mcp python api-to-mcp tool-generation asgi openapi auto-discovery

⚙ Agent Friendliness

/ 100

Can an agent use this?

🔒 Security

/ 100

Is it safe for agents?

⚡ Reliability

/ 100

Does it work consistently?

Score Breakdown

⚙ Agent Friendliness

MCP Quality

Documentation

Error Messages

Auth Simplicity

Rate Limits

🔒 Security

TLS Enforcement

Auth Strength

Scope Granularity

Dep. Hygiene

Secret Handling

Exposes existing FastAPI routes as MCP tools. Security depends entirely on underlying FastAPI app auth. Use OAuth2/API key on FastAPI routes before exposing via MCP.

⚡ Reliability

Uptime/SLA

Version Stability

Breaking Changes

Error Recovery

Best When

You already have a FastAPI application and want to expose its endpoints as MCP tools with minimal effort. The zero-config approach and native FastAPI auth integration make this the path of least resistance.

Avoid When

You're not using FastAPI, need to support non-Python backends, or require MCP tools that don't map cleanly to REST endpoints.

Use Cases

• Exposing an existing FastAPI application to AI agents without writing MCP-specific code
• Giving Claude or other LLM clients access to internal REST APIs through MCP
• Bridging existing microservices into the MCP ecosystem with minimal refactoring
• Adding AI agent access to FastAPI apps while reusing existing auth via Depends()

Not For

• Non-FastAPI Python frameworks (Flask, Django) - FastAPI-specific
• Non-Python APIs - Python only
• Complex MCP workflows requiring custom tool logic beyond endpoint mapping

Interface

REST API

Yes

GraphQL

gRPC

MCP Server

Yes

SDK

Yes

Webhooks

Authentication

Methods: fastapi_depends

OAuth: No Scopes: No

Leverages FastAPI's native Depends() dependency injection for auth. Whatever auth your FastAPI app already uses (API keys, OAuth, JWT) carries through to MCP tools automatically.

Pricing

Model: open_source

Free tier: Yes

Requires CC: No

MIT licensed. Optional managed hosting available through Tadata.com.

Agent Metadata

Pagination

unknown

Idempotent

Unknown

Retry Guidance

Not documented

Known Gotchas

⚠ Only works with FastAPI - not a general-purpose API-to-MCP bridge
⚠ Auth passthrough requires understanding FastAPI's Depends() pattern
⚠ Endpoint filtering/selection configuration may be needed for large APIs
⚠ ASGI transport means it must run in-process with the FastAPI app

Alternatives

mcpify openapi-mcp-server custom MCP server implementation

Full Evaluation Report

Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for FastAPI-MCP.

$99

API endpoint ↗ Agent guide ↗ Report inaccuracy

Scores are editorial opinions as of 2026-03-06.