Mutmut MCP

A Model Context Protocol (MCP) server for managing mutation testing with mutmut. This tool provides a set of programmatic APIs for running mutation tests, analyzing results, and improving test coverage in Python projects.

Features

• Run mutation testing sessions on any Python module or package
• Show overall mutation testing results and surviving mutations
• Suggest areas needing better test coverage
• Rerun mutmut on specific survivors or all survivors
• Clean mutmut cache
• Designed for automation and integration with other MCP tools

Install

# Run directly from GitHub (no install needed)
uvx --from git+https://github.com/wdm0006/mutmut-mcp mutmut-mcp

# Or install from source
git clone https://github.com/wdm0006/mutmut-mcp
cd mutmut-mcp
uv sync
uv run mutmut_mcp.py

Installing via Smithery

To install mutmut-mcp for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @wdm0006/mutmut-mcp --client claude

MCP Client Configuration

{
  "mcpServers": {
    "mutmut": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/wdm0006/mutmut-mcp", "mutmut-mcp"]
    }
  }
}

API / Tools

The following tools are available:

• run_mutmut(target, test_command="pytest", options="", venv_path=None) – Run mutation testing
• show_results(venv_path=None) – Show overall results
• show_survivors(venv_path=None) – List surviving mutations
• generate_test_suggestion(venv_path=None) – Suggest areas needing better test coverage
• rerun_mutmut_on_survivor(mutation_id=None, venv_path=None) – Rerun mutmut on survivors
• clean_mutmut_cache(venv_path=None) – Clean mutmut cache

License

This project is licensed under the MIT License. See LICENSE for details.