openrpc

This MCP server exposes JSON-RPC functionality via OpenRPC. It provides two built-in tools: rpc_call, which lets you invoke arbitrary JSON-RPC methods against a target server by specifying the URL, method name, and parameters; and rpc_discover, which uses OpenRPC's rpc.discover to list all available methods on a given server. Together, these tools enable you to programmatically discover and call methods defined by an OpenRPC specification, with results returned in JSON format. Use rpc_discover to understand the available API surface, then use rpc_call to perform specific method invocations and receive structured results suitable for downstream automation or integration workflows.

Prerequisites:

• Node.js and npm installed on your system
• Access to install npm packages (the server runs via npx using the published package)

Installation steps:

1. Install dependencies and build the server (from the repository root):

npm install

2. Build the server (produces production-ready artifacts as defined by the project):

npm run build

3. (Optional for development) Enable auto-rebuild during development:

npm run watch

Usage with Claude Desktop (example config shown in the repository):

• Update Claude Desktop configuration to include this MCP server, e.g.:

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

Note: The server communicates over standard input/output (stdio), so it can be integrated with various host environments that support MCP.

Helpful notes:

• The MCP server communicates over stdio, which can complicate debugging. Use the MCP Inspector tool for debugging and a browser-based interface when provided: npm run inspector.
• The repository shows an example Claude Desktop configuration; if you are integrating with Claude, place the config at the standard Claude config path for macOS or Windows as documented in the README.
• The available tools are rpc_call and rpc_discover. Prepare your OpenRPC-compatible target URL for discovery, then craft JSON-RPC requests to perform method calls.
• No additional environment variables are strictly required for the basic operation, but you may need to configure proxies or authentication credentials depending on your target RPC server.