SSH Real MCP Server

A Model Context Protocol (MCP) server that enables SSH remote command execution by delegating entirely to the system ssh binary. This means ssh-agent, ProxyCommand, ~/.ssh/config, jump hosts, and every other OS-level SSH feature work out of the box — no Node.js crypto, no native addons.

How it works

Instead of implementing the SSH protocol in Node.js, this server spawns ssh as a child process and pipes the output back to the MCP client. Authentication, key discovery, and connection routing are handled by your OS, exactly as if you ran ssh yourself in a terminal.

Requirements: ssh must be installed and available in PATH (standard on macOS and Linux).

Features

Zero auth config — uses your existing ssh-agent, ~/.ssh/config, and key files automatically
ProxyCommand / jump hosts — works natively, no special parameters needed
Connectivity test — ssh_test tool to verify reachability before running commands
Argument injection protection — host and username are validated before being passed to ssh
Configurable timeout — commands are killed and an error is returned if they exceed the timeout
Detailed results: stdout, stderr, and exit code

Installation

From npm

Terminal

npm install -g @danielecr/realssh-mcp

From source

bash

git clone https://github.com/danielecr/realssh-mcp.git
cd realssh-mcp
npm install
npm run build

VS Code / Copilot configuration

After installing the package globally, add the server to your MCP configuration. In VS Code, open the MCP config file via Command Palette → MCP: Open User Configuration and add:

config.json

{
  "servers": {
    "realssh": {
      "type": "stdio",
      "command": "realssh-mcp"
    }
  }
}

Then run MCP: List Servers to verify the server is active.

Tools

`ssh_execute`

Execute a command on a remote server via SSH.

Parameters:

host (string, required): SSH server hostname or IP address
command (string, required): Command to execute on the remote server
username (string, optional): SSH username. Defaults to the current OS user
port (number, optional): SSH server port (default: 22)
timeout (number, optional): Command timeout in milliseconds (default: 30000)
agentForward (boolean, optional): Enable SSH agent forwarding -A (default: false)
extraArgs (string[], optional): Extra SSH arguments (e.g., ["-o", "StrictHostKeyChecking=no"])

Example:

config.json

{
  "host": "prod-web-01",
  "command": "df -h"
}

config.json

{
  "host": "192.168.1.100",
  "username": "deploy",
  "command": "systemctl status nginx"
}

`ssh_test`

Test SSH connectivity to a remote host (runs echo ok and checks the response).

Parameters:

host (string, required): SSH server hostname or IP address
username (string, optional): SSH username
port (number, optional): SSH server port (default: 22)
extraArgs (string[], optional): Extra SSH arguments

Host configuration

Hosts, aliases, jump hosts, and identity files are configured in ~/.ssh/config — not in the MCP server. This is intentional: the OS ssh binary reads that file natively.

Example ~/.ssh/config:

sshconfig

Host prod
    HostName prod.example.com
    User deploy
    ProxyJump bastion

Host bastion
    HostName bastion.example.com
    User admin
    IdentityFile ~/.ssh/bastion_ed25519

With the above config, "host": "prod" works with no extra parameters.

Security considerations

Commands are executed on remote systems with the privileges of the SSH user — ensure proper access controls on the remote side.
BatchMode=yes is set by default, preventing the ssh process from hanging on interactive prompts.
Host and username inputs are validated to prevent SSH option injection.
Command output may contain sensitive data; treat it accordingly.

License

MIT