Zero-Code MCP Server
for Any Web API.

Just an openapi.yaml — instantly MCP-ready.
An ultra-lightweight OpenAPI proxy with a built-in OAuth 2.1 server.

View on GitHub View on npm Deploy to Cloudflare

# Option A: published on npm, no install needed — try it now npx beefchicken-mcp --openapi ./openapi.yaml # Option B: clone the repo and deploy to Cloudflare Workers npm install npm run generate # Auto-generate tool definitions npx wrangler deploy # Option C: also runs on Docker (image distributed via GHCR) docker run -p 3000:3000 \ -e HOST=0.0.0.0 \ -e ALLOWED_HOSTS=127.0.0.1,localhost \ -e API_BASE_URL=https://api.example.com \ -v $(pwd)/docs/openapi.yaml:/app/docs/openapi.yaml:ro \ ghcr.io/watanabebashi/beefchicken-mcp # Done! Ready to use right away from Claude or Cursor.

For Solo Developers

Turn your own web app's API straight into MCP.

If your web app or SaaS already has a REST API, that's all you need. Just drop in an openapi.yaml and deploy to Cloudflare Workers, and you'll have an MCP server with OAuth 2.1 authentication running in minutes.

OpenAPI conversion → Workers deploy → Built-in OAuth 2.1

One stop, and your API is enchanted.

Why BeefChicken MCP?

Skip tedious tool definitions and handler implementations entirely

Zero Lines of Code

No need to write MCP handlers in TypeScript or Python. Just swap in your API spec as docs/openapi.yaml and it's automatically published as a tool.

Instant Claude.ai Web Support

Ships with a lightweight built-in OAuth 2.1 server for clients that can't supply an API key directly. Connect instantly as a custom connector in the web version of Claude.

Zero Server Costs

Native support for Cloudflare Workers means deployment in seconds. Get a robust MCP server for free, as long as you stay within the free tier.

Minimal Footprint

YAML parsing and $ref resolution are processed into static JSON before deploy or at container startup, eliminating parsing overhead at request time entirely.

Published on npm, Runtime-Agnostic

Run it instantly with npx beefchicken-mcp — no install required. Also runs on Node.js hosting and Docker (distributed via GHCR), in addition to Cloudflare Workers.

Comparison

How it stacks up against existing approaches to building MCP servers

Feature	Manual Implementation (SDK)	Most MCP Frameworks	BeefChicken MCP
Code required	Required (a lot)	Required (a little)	Not required (0 lines)
OpenAPI support	Manual conversion required	Handler implementation required	Just swap the file
Built-in OAuth 2.1	Build it yourself	Build it yourself	Built in
Runtime	Bring your own	Framework-dependent	npx / Node.js / Docker / Cloudflare Workers