mcp-http-proxy

Name: mcp-http-proxy
Author: spontaneous-order

@spontaneous-order

About mcp-http-proxy

An HTTP/SSE proxy server for Model Context Protocol (MCP) applications using stdio. Supports raw JSON-RPC commands via HTTP and implements direct stdio communication without an MCP SDK.

#mcp-http-proxy #http-proxy #json-rpc

Basic information

Config

Add this server to your MCP-compatible client using the configuration below.

{
  "mcpServers": {
    "mcp-http-proxy": {
      "command": "node",
      "args": [
        "rpc-proxy-worker.js"
      ]
    }
  }
}

Tools

No tools detected

We auto-extract tools from the README. The maintainer can list them under a ## Tools heading to populate this section.

Overview

What is mcp-http-proxy?

mcp-http-proxy is an HTTP/SSE intermediary proxy server that manages a stdio-based MCP (Model Context Protocol) server process and exposes its tools and resources over standard HTTP and Server-Sent Events. It is designed for developers and applications that need to interact with MCP processes without handling stdio directly.

How to use mcp-http-proxy?

Run the script rpc-proxy-worker.js with Node.js (no additional install steps besides having Node.js). The server starts on port 3005 by default, serving a web dashboard at http://localhost:3005. Clients interact via HTTP endpoints (e.g., GET /tool/:toolName, POST /rpc/raw/command) or by connecting to the SSE endpoint at /sse.

Key features of mcp-http-proxy

Manages the lifecycle of a child MCP server process.
Provides HTTP endpoints for tools and raw JSON-RPC commands.
Delivers real-time events via Server-Sent Events (SSE).
Includes a web dashboard for tool discovery and debugging.
Translates URL query parameters into JSON-RPC tools/call requests.
Supports multiple client types (curl, browser, scripts).
Handles parameter validation and error relay.
Provides debugging endpoints for raw message history and logs.

Use cases of mcp-http-proxy

Expose a local stdio-only MCP server to web applications via HTTP.
Allow multiple HTTP clients to share a single managed MCP process.
Enable programmatic interaction with MCP tools using standard REST/SSE.
Debug and test MCP server responses without writing a custom client.

FAQ from mcp-http-proxy

What runtime does mcp-http-proxy require?

The proxy runs on Node.js. No other runtime dependencies are mentioned; the MCP server it manages is expected to be a separate process.

How do clients communicate with the MCP server through the proxy?

Clients send HTTP requests to endpoints like /rpc/raw/command (raw JSON-RPC) or /tool/:toolName (URL parameter style). The proxy forwards these as JSON-RPC commands to the child MCP process via stdin, and returns the response from stdout. Asynchronous events are pushed over SSE.

What endpoints does mcp-http-proxy provide?

The main endpoints are: GET / (dashboard), GET /tools, GET /tool/:toolName, POST /rpc/raw/command, GET /sse, GET /help, and several debugging endpoints (/rpc/command, /rpc/raw, /debug).

How does the proxy handle errors?

It returns HTTP status codes (e.g., 404 for unknown tools, 400 for invalid parameters) and validates parameters for /tool/:toolName. Errors from the MCP process are relayed back in HTTP responses or pushed via SSE.