Genotoxic

Takes your mutation testing results and stops you from writing tests for the wrong reasons. It runs Trailmark to build a call graph, then cross-references survived mutants with code structure to sort them into false positives (dead code, logging strings), missing unit tests, or functions complex enough to need fuzzing instead. The necessist integration finds weak assertions by removing test statements to see what still passes. Honest take: mutation testing generates noise, and most teams either ignore it or waste time on harmless mutants. This actually triages the output using reachability and data flow, which is the only way to make mutation testing actionable at scale. Requires trailmark and a language-specific mutation framework installed upfront.

Install to Claude Code

npx -y skills add trailofbits/skills --skill genotoxic --agent claude-code