Atrax (MCP Proxy) MCP server

Atrax is a proxy for Model Context Protocol (MCP) servers that aggregates multiple MCP servers and presents them as a single unified interface. It funnels resources from multiple servers into one, allowing clients to interact with a consolidated MCP service while Atrax handles the distribution of requests and responses behind the scenes.

Features

• Resource Aggregation: Combine resources from multiple servers with configurable conflict resolution
• Transparent Proxying: Present a unified MCP server interface to clients
• Protocol Compliance: Strict adherence to the MCP protocol specification
• Multiple Transport Types: Support for STDIO, HTTP/SSE, and Docker transports
• Enhanced Error Handling: Detailed error reporting with contextual information
• Web Integration: HTTP/SSE transport for browser and web-based clients
• Authentication Support: Token-based authentication for securing server access

Installation

To get Atrax up and running, follow these steps:

# Clone the repository
git clone https://github.com/yourusername/atrax.git
cd atrax

# Setup development environment
direnv allow  # Sets up Python venv and pre-commit
npm install

# Build the project
npm run build

Basic Usage

Starting the Server

You can run the server with or without authentication:

# Run the server (no authentication)
npm run serve

# Run with token authentication
npm run serve:auth

Example Servers

Atrax includes several example server implementations that you can use to test functionality:

STDIO-based Servers

# Run a simple Memory server
npm run memory-server

# Run a basic Echo server
npm run echo-server

HTTP/SSE-based Server

# Run an HTTP Echo server
npm run http-echo-server

Client Examples

To connect to the example servers:

# Connect to STDIO Echo server
npm run echo-client

# Connect to STDIO Memory server
npm run memory-client

# Connect to HTTP/SSE Echo server
npm run http-echo-client

Testing

To verify your installation is working correctly:

# Run smoke tests
npm run test:smoke

HTTP/SSE Transport

Atrax provides HTTP/SSE transport which is particularly useful for browser and web-based clients. This transport method allows Atrax to communicate with clients over HTTP using Server-Sent Events for real-time updates.

Authentication

Token-based authentication can be enabled to secure access to your Atrax server. When running with authentication:

npm run serve:auth

Clients will need to provide valid authentication tokens to access the server's resources.

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "atrax" '{"command":"npx","args":["-y","atrax"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "atrax": {
            "command": "npx",
            "args": [
                "-y",
                "atrax"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "atrax": {
            "command": "npx",
            "args": [
                "-y",
                "atrax"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect