The MCP-to-OpenAPI proxy server lets you use tool servers implemented with MCP (Model Context Protocol) directly via standard REST/OpenAPI APIs—no need to manage unfamiliar or complicated custom protocols. If you’re an end-user or application developer, this means you can interact easily with powerful MCP-based tooling directly through familiar REST-like endpoints. (View Highlight)
While MCP tool servers are powerful and flexible, they commonly communicate via standard input/output (stdio)—often running on your local machine where they can easily access your filesystem, environment, and other native system capabilities. (View Highlight)
That’s a strength—but also a limitation.
If you want to deploy your main interface (like Open WebUI) on the cloud, you quickly run into a problem: your cloud instance can’t speak directly to an MCP server running locally on your machine via stdio. (View Highlight)
That’s where mcpo comes in with a game-changing solution.
MCP servers typically rely on raw stdio communication, which is:
• 🔓 Inherently insecure across environments
• ❌ Incompatible with most modern tools, UIs, or platforms
• 🧩 Lacking critical features like authentication, documentation, and error handling
The mcpo proxy eliminates those issues—automatically:
• ✅ Instantly compatible with existing OpenAPI tools, SDKs, and clients
• 🛡 Wraps your tools with secure, scalable, and standards-based HTTP endpoints
• 🧠 Auto-generates interactive OpenAPI documentation for every tool, entirely config-free
• 🔌 Uses plain HTTP—no socket setup, daemon juggling, or platform-specific glue code (View Highlight)
So even though adding mcpo might at first seem like “just one more layer”—in reality, it simplifies everything while giving you:
• Better integration ✅
• Better security ✅
• Better scalability ✅
• Happier developers & users ✅
✨ With mcpo, your local-only AI tools become cloud-ready, UI-friendly, and instantly interoperable—without changing a single line of tool server code. (View Highlight)
🍃 How It Works (Technical Summary)
• Dynamic Schema Discovery & Endpoints: At server startup, the proxy connects to the MCP server to query available tools. It automatically builds FastAPI endpoints based on the MCP tool schemas, creating concise and clear REST endpoints.
• OpenAPI Auto-documentation: Endpoints generated are seamlessly documented and available via FastAPI’s built-in Swagger UI (/docs). No extra doc writing required.
• Asynchronous & Performant: Built on robust asynchronous libraries, ensuring speed and reliability for concurrent users. (View Highlight)
📚 Under the Hood:
• FastAPI (Automatic routing & docs generation)
• MCP Client (Standard MCP integration & schema discovery)
• Standard JSON over HTTP (Easy integration) (View Highlight)