소개
The Mutation Test Runner skill empowers Claude to perform advanced mutation testing, a technique that evaluates the actual effectiveness of a test suite by injecting small, intentional logic errors into the source code. Unlike traditional code coverage which only measures which lines were executed, this skill calculates a mutation score by determining if your tests are capable of 'killing' these mutants. It helps developers identify 'surviving mutants'—specific logic paths that are covered by tests but not actually validated—ensuring mission-critical code is robustly protected against regressions.