Crate mcp_runner

MCP Runner

A Rust library for running and interacting with Model Context Protocol (MCP) servers.

Overview

MCP Runner provides functionality to:

• Start and manage MCP server processes
• Communicate with MCP servers using JSON-RPC
• List and call tools provided by MCP servers
• Access resources exposed by MCP servers
• Optionally proxy SSE (Server-Sent Events) to the servers for external clients

Basic Usage

use mcp_runner::{McpRunner, Result};
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<()> {
    // Create a runner from config file
    let mut runner = McpRunner::from_config_file("config.json")?;

    // Start all configured servers
    let server_ids = runner.start_all_servers().await?;

    // Or start a specific server
    let server_id = runner.start_server("fetch").await?;

    // Get a client to interact with the server
    let client = runner.get_client(server_id)?;

    // Initialize the client
    client.initialize().await?;

    // List available tools
    let tools = client.list_tools().await?;
    println!("Available tools: {:?}", tools);

    // Call a tool
    let args = json!({
        "url": "https://modelcontextprotocol.io"
    });
    let result: Value = client.call_tool("fetch", &args).await?;

    println!("Result: {:?}", result);

    Ok(())
}

Features

• Server Management: Start, stop, and monitor MCP servers
• JSON-RPC Communication: Communicate with MCP servers using JSON-RPC
• Configuration: Configure servers through JSON config files
• Error Handling: Comprehensive error handling
• Async Support: Full async/await support
• SSE Proxy: Support for SSE proxying with authentication and CORS

License

This project is licensed under the terms in the LICENSE file.

Re-exports

pub use client::McpClient;

pub use config::Config;

pub use error::Error;

pub use error::Result;

pub use server::ServerId;

pub use server::ServerProcess;

pub use server::ServerStatus;

pub use sse_proxy::SSEProxyHandle;

Modules

client

Client module for interacting with MCP servers.

config

Configuration module for MCP Runner.

error

Error handling module for MCP Runner.

server

Server management module for MCP Runner.

sse_proxy

SSE proxy implementation for MCP servers using Actix Web.

transport

Transport module for communication with MCP servers.

Structs

McpRunner

Configure and run MCP servers