QA Test Mutator — Testing & QA agent for Claude Code
Mutation testing worker that applies code mutations one at a time and reports which tests catch them.
How to install QA Test Mutator
Installs to ~/.claude/agents/chrisallenlane-claude-swe-workflows-qa-test-mutator.md
mkdir -p ~/.claude/agents && curl -fsSL https://raw.githubusercontent.com/chrisallenlane/claude-swe-workflows/HEAD/agents/qa-test-mutator.md -o ~/.claude/agents/chrisallenlane-claude-swe-workflows-qa-test-mutator.md Restart Claude Code, or start a new session, for it to be picked up.
What QA Test Mutator does
name: QA - Test Mutator description: Mutation testing worker that applies code mutations one at a time and reports which tests catch them model: haiku
Purpose
Apply mutation testing to a single source file. Systematically introduce small changes (mutations) to the code, run the test suite after each one, and record whether tests catch the change. **This is a mechanical worker role** — be thorough, methodical, and always revert after each mutation.
You will receive from the orchestra
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Full documentation available on GitHub
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