MCP Terminal Server

A secure terminal execution server implementing the Model Context Protocol (MCP). This server provides controlled command execution capabilities with security features and resource limits.

Features

Command Execution: Execute shell commands with output capture and error handling
Security Controls: Restrict allowed commands and prevent command injection
Resource Controls:
- Command timeouts
- Maximum output size limits
MCP Protocol Support:
- Standard MCP message format
- Capability advertisement
- Streaming output support

Related MCP server: Terminal Controller for MCP

Development

Local Setup

# Clone the repository git clone https://github.com/RinardNick/mcp-terminal.git cd mcp-terminal # Create and activate virtual environment using uv uv venv source .venv/bin/activate # or .venv\Scripts\activate on Windows # Install development dependencies uv pip install -e ".[dev]"

Publishing to PyPI

# Build the package uv pip install build python -m build # Upload to PyPI uv pip install twine python -m twine upload dist/*

Testing with MCP Inspector

The MCP Inspector tool can be used to test the server implementation:

# Install inspector npm install -g @modelcontextprotocol/inspector # Test server npx @modelcontextprotocol/inspector python3 src/mcp_terminal/server.py --allowed-commands "python,pip,git,ls,cd"

Running Tests

# Run all tests pytest tests/ # Run specific test file pytest tests/test_terminal.py # Run with coverage pytest --cov=mcp_terminal tests/

Using with Claude Desktop

Once the package is published to PyPI:

Install UV (if not already installed):
pip install uv
Install the Package using UV:
uv pip install mcp-terminal
Configure Claude Desktop: Edit your Claude Desktop config file (typically at ~/Library/Application Support/Claude/claude_desktop_config.json on macOS):
{ "mcpServers": { "terminal": { "command": "uv", "args": [ "pip", "run", "mcp-terminal", "--allowed-commands", "python,pip,git,ls,cd", "--timeout-ms", "30000", "--max-output-size", "1048576" ] } } }

Protocol Implementation

The server implements the Model Context Protocol (MCP) with the following capabilities:

Capabilities Advertisement

{ "protocol": "1.0.0", "name": "terminal", "version": "1.1.0", "capabilities": { "execute": { "description": "Execute a terminal command", "parameters": { "command": { "type": "string", "description": "The command to execute" } }, "returns": { "type": "object", "properties": { "exitCode": { "type": "number" }, "stdout": { "type": "string" }, "stderr": { "type": "string" }, "startTime": { "type": "string" }, "endTime": { "type": "string" } } } } } }

Message Format

Request:

{ "type": "execute", "data": { "command": "echo 'hello world'" } }

Response:

{ "type": "result", "data": { "command": "echo 'hello world'", "exitCode": 0, "stdout": "hello world\n", "stderr": "", "startTime": "2024-01-20T12:34:56.789Z", "endTime": "2024-01-20T12:34:56.790Z" } }

Error:

{ "type": "error", "data": { "message": "command not allowed" } }

Security Considerations

Command Validation:
- Only allowed commands can be executed
- Shell operators are blocked
- Command injection attempts are prevented
Resource Protection:
- Command timeouts prevent hanging
- Output size limits prevent memory exhaustion
- Error handling for all failure cases
Best Practices:
- Always set allowed-commands in production
- Use conservative timeout and size limits
- Monitor command execution logs