MCP Server: Linux Command-Line Executor

A Node.js/NPM-based MCP server that:

• Exposes an HTTP SSE endpoint for MCP clients
• Provides an exec tool that runs arbitrary Linux command lines on the host

Security note: Intended to run inside a Docker container with trusted clients. The exec tool provides unrestricted command execution.

Requirements

• nvm and a Node version that matches .nvmrc
• npm

Setup

cd /Users/manuel/git/github/dx-tooling/maas/maas-mcpserver-linux-cmd-line
nvm use
npm install

Running in SSE mode (HTTP)

• Dev (TypeScript):

nvm use
PORT=3000 npm run dev:http

• Build + Run (JavaScript):

nvm use
npm run build
PORT=3000 npm run start:http

The server exposes:

• GET /health → Health check endpoint (returns HTTP 200 with service status)
• GET /mcp → Establishes SSE stream (deprecated HTTP+SSE transport)
• POST /messages?sessionId=<id> → JSON-RPC messages from the client

Use an MCP-compatible client to connect via SSE. Manual interaction is non-trivial because the sessionId is provided over the SSE stream.

Health Check

The server provides a health check endpoint at /health that returns HTTP 200 when the service is running:

curl http://localhost:3000/health

Response:

{
  "status": "healthy",
  "timestamp": "2025-09-10T06:50:40.772Z",
  "service": "maas-mcpserver-linux-cmd-line",
  "version": "1.0.0",
  "activeSessions": 0
}

Running in stdio mode

• Dev:

nvm use
npm run dev:stdio

• Build + Run:

nvm use
npm run build
npm run start:stdio

Tool: exec

• Name: exec
• Description: Execute a Linux command on the host system
• Input schema:
  • command (string, required): Full shell command line
  • cwd (string, optional): Working directory
  • env (record<string,string>, optional): Extra environment variables
• Output schema (structured):
  • exitCode (number)
  • stdout (string)
  • stderr (string)

While the command runs, stdout/stderr chunks are forwarded as MCP logging messages over the current session.

Quality

nvm use
npm run quality

Notes

• Default port is 3000 when PORT is not set.
• SSE transport in this project is provided for compatibility/testing (deprecated protocol). For production, prefer stdio or modern transports with compatible clients.