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

Installation

Installing via Smithery

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

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

Manual Installation

Clone the repository:

git clone https://github.com/wdm0006/mutmut-mcp.git
cd mutmut-mcp

Install dependencies:

python3 -m venv .venv
source .venv/bin/activate
pip install -U pip
pip install mcp[cli] mutmut

Usage

You can run the MCP server directly:

python mutmut_mcp.py

Or use with uv:

uv run --with mcp --with mutmut mutmut_mcp.py

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.