OpenRPC MCP Server (Updated)

A Model Context Protocol (MCP) server that provides JSON-RPC functionality through OpenRPC.

Note: This is an updated fork of the original openrpc-mcp-server by shanejonas. The primary improvement is the updated @modelcontextprotocol/sdk dependency (v1.18.1) for compatibility with newer MCP clients.

Original Work

This package is based on the excellent work by:

• Original Author: shanejonas
• Original Repository: https://github.com/shanejonas/openrpc-mpc-server
• Original npm Package: openrpc-mcp-server

What's Updated

• ✅ Updated @modelcontextprotocol/sdk from v0.6.0 to v1.18.1 for compatibility with newer MCP clients
• ✅ Maintained full backward compatibility with existing features

https://github.com/user-attachments/assets/3447175a-f921-4ded-8250-b611edb2fb67

Features

Tools

• rpc_call - Call arbitrary JSON-RPC methods
  • Specify server URL, method name, and parameters
  • Returns JSON-formatted results
• rpc_discover - Discover available JSON-RPC methods
  • Uses OpenRPC's rpc.discover specification
  • Lists all methods on a given server

Development

Install dependencies:

npm install

Build the server:

npm run build

For development with auto-rebuild:

npm run watch

Installation

npm

Install the updated package:

npm install -g openrpc-mcp-server-updated

Or use with npx:

npx openrpc-mcp-server-updated

Claude Desktop Configuration

To use with Claude Desktop, add the server config:

On MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json On Windows: %APPDATA%/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "openrpc": {
      "command": "npx",
      "args": ["-y", "openrpc-mcp-server-updated"]
    }
  }
}

Debugging

Since MCP servers communicate over stdio, debugging can be challenging. We recommend using the MCP Inspector:

npm run inspector

The Inspector will provide a URL to access debugging tools in your browser.