ShellSAFE

A Node.js implementation of the Model Context Protocol (MCP) that provides secure shell command execution capabilities. This server allows AI models to execute shell commands in a controlled environment with built-in security measures. Easily integrates with Claude Desktop for connecting Claude with your shell.

Features

• MCP-compliant server implementation
• Secure command execution with blacklist protection
• Command existence validation
• Standard I/O based transport
• Error handling and graceful shutdown

Installation

Run npx mcp-shell.

To add it to Claude Desktop, run npx mcp-shell config. Or add npx -y mcp-shell to your config manually.

Start (or restart) Claude Desktop and you should see the MCP tool listed on the landing page.

Security Features

The server implements several security measures:

1. Command Blacklisting

• Prevents execution of dangerous system commands
• Blocks access to critical system modifications
• Protects against file system destruction
• Prevents privilege escalation

1. Command Validation
2. Verifies command existence before execution
3. Validates against the blacklist
4. Returns clear error messages for invalid commands

Available Tools

The server provides one tool:

run_command

Executes a shell command and returns its output.

Input Schema:

{
"type": "object",
"properties": {
"command": { "type": "string" }
}
}

Response:

• Success: Command output as plain text
• Error: Error message as plain text

Blacklisted Commands

The following command categories are blocked for security:

• File System Destruction Commands (rm, rmdir, del)
• Disk/Filesystem Commands (format, mkfs, dd)
• Permission/Ownership Comm