MCP Tunnel

A simple MCP (Model Context Protocol) server that allows accessing the command line of a VM machine. When started, it also tunnels the host to the web so it can be accessed via MCP.

Features

Execute shell commands on a VM through MCP
Web-based terminal interface for VM interaction
Automatic tunneling to make the VM accessible from anywhere
WebSocket-based real-time communication

Prerequisites

Node.js (v18 or newer)

Installation and Usage

Running with npx (no installation)

npx mcp-cli

Global Installation

npm install -g mcp-cli
mcp-cli

Local Development

# Clone repository
git clone [repository-url]
cd mcp-cli

# Install dependencies
npm install

Development

Run the development server with hot-reloading for both backend and frontend:

npm run dev

Building

Build both the frontend and backend for production:

npm run build-all

Usage

Start the MCP server:

# Start with automatic tunneling
npm start

# Start without automatic tunneling
npm start -- --no-tunnel

This will build the project and start the server. By default, a tunnel will be created automatically. Use the --no-tunnel flag to disable automatic tunneling.

The server will start and provide output on stderr (to avoid interfering with MCP communication on stdout)
Use MCP to interact with the server using the following tools:

Available MCP Tools

execute_command: Run a shell command on the VM
- Parameters: { "command": "your shell command" }
start_tunnel: Create a web tunnel to access the VM interface
- Parameters: { "port": 8080, "subdomain": "optional-subdomain" }

Web Interface

After starting the tunnel, you can access the web-based terminal interface at the URL provided by the tunnel. This interface allows you to:

Execute commands directly in the VM
See command outputs in real-time
Interact with the VM from any device with web access

Environment Variables

Create a .env file to configure the server:

# Server configuration
PORT=8080

# Localtunnel configuration
LOCALTUNNEL_SUBDOMAIN=your-preferred-subdomain

Security Considerations

This tool provides direct access to your VM's command line. Consider these security practices:

Use strong authentication mechanisms before exposing the tunnel
Limit the commands that can be executed through proper validation
Consider running in a restricted environment
Do not expose sensitive information through the tunnel

Usage

Start the MCP server:

# Start with automatic tunneling npm start # Start without automatic tunneling npm start -- --no-tunnel

This will build the project and start the server. By default, a tunnel will be created automatically. Use the --no-tunnel flag to disable automatic tunneling.

The server will start and provide output on stderr (to avoid interfering with MCP communication on stdout)

Use MCP to interact with the server using the following tools:

Available MCP Tools

execute_command: Run a shell command on the VM

Parameters: { "command": "your shell command" }

start_tunnel: Create a web tunnel to access the VM interface

Parameters: { "port": 8080, "subdomain": "optional-subdomain" }

Security Considerations

This tool provides direct access to your VM's command line. Consider these security practices:

Use strong authentication mechanisms before exposing the tunnel

Limit the commands that can be executed through proper validation

Consider running in a restricted environment

Do not expose sensitive information through the tunnel