MCP Server Proxy

🚀 MCP Server Proxy

A proxy server that can connect to multiple MCP servers and provides a unified interface for tools to access.

🚀 Quick Start

The MCP Server Proxy is a useful tool that allows you to connect to multiple MCP servers and provides a unified interface for tools. It offers flexible configuration and running modes to meet different needs.

✨ Features

• Connect to multiple MCP servers simultaneously.
• Support multiple configuration files.
• Prefix tool names with the server name.
• Run in either "stdio" or "SSE" mode.
• Manage based on configuration files.

📦 Installation

npm install

💻 Usage Examples

Basic Usage

Command-line Options

The server can be started with the following command-line options:

# Start with default settings
node dist/server.js

# Start with a specific configuration file
node dist/server.js --profile developer
# Or
node dist/server.js -p developer

# Start in SSE mode
node dist/server.js --mode sse
# Or
node dist/server.js -m sse

# Start in SSE mode with a custom port and host
node dist/server.js --mode sse --port 8080 --host 0.0.0.0

# Combine options
node dist/server.js --profile developer --mode sse --port 8080

Available options:

• -p, --profile <name>: Specify the name of the configuration file to use (default is "default").
• -m, --mode <mode>: Choose between "stdio" or "sse" mode (default is "stdio").
• --port <number>: Set the port for SSE mode (default is 3000).
• --host <host>: Set the host for SSE mode (default is "localhost").

Get help:

node dist/server.js --help

Tool Naming Convention

Tool names are prefixed with the name of their server. For example:

• The tool "read_file" from the "filesystem" server becomes "filesystem_read_file".
• The tool "get_pods" from the "kubernetes" server becomes "kubernetes_get_pods".

SSE Mode Endpoints

In SSE mode, the server exposes the following endpoints:

• GET /sse: Establish an SSE connection.
• POST /messages: Handle tool requests (requires the sessionId query parameter).

Example SSE client usage:

const eventSource = new EventSource("http://localhost:3000/sse");
eventSource.onmessage = (event) => {
  console.log("Received:", event.data);
};

Advanced Usage

Configuration

Create a file named config.<profile>.json for each configuration file, for example:

// config.developer.json
{
  "mcpServers": {
    "kubernetes": {
      "command": "npx",
      "args": ["mcp-server-kubernetes"]
    }
  }
}

// config.personal.json
{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "/Users/mirilale/Desktop"
      ]
    }
  }
}

📚 Documentation

Error Handling

The server provides detailed error information, including:

• Configuration file loading errors.
• Server connection failures.
• Tool not found errors.
• Server disconnection errors.

All error messages include the current configuration file name for better context.

Development

# Install dependencies
npm install

# Build the project
npm run build

# Run in development mode (stdio mode)
npm run dev:stdio:developer
# Or
npm run dev:sse:developer

# Use the mpc inspection tool
npm run inspect

📄 License

MIT