qa-mutation-effectiveness

Inject bugs into High/Critical risk modules and check test suite catch rates.

Updated May 28, 2026

Search Tags:#code quality #test automation #QA #mutation testing #test suite effectiveness

Ready to run

npx skills add https://github.com/SensLiao/Claude-code-setting --skill qa-mutation-effectiveness

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: qa-mutation-effectiveness
Source: https://github.com/SensLiao/Claude-code-setting/tree/main/skills/qa-mutation-effectiveness
Command: npx skills add https://github.com/SensLiao/Claude-code-setting --skill qa-mutation-effectiveness

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires stryker-mutator, cargo-mutants, mutmut, pitest, and includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill identifies whether existing tests catch injected bugs, ensuring test suite effectiveness without assessing code correctness.

Core Features & Use Cases

Mutation Testing: Measures test suite effectiveness by injecting bugs and checking if they are caught by the tests.
Language Support: Supports multiple languages (JS/TS, Rust, Python, Java/JVM) with various mutation testing tools.
Risk-Based Scoping: Limited to High/Critical risk modules for cost control.
Threshold-based Gate: Uses mutation-score thresholds to control build gates.

Quick Start

Run mutation testing for a test suite using the qa-mutation-effectiveness skill.

Frequently Asked Questions about qa-mutation-effectiveness

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How does mutation testing measure test suite effectiveness?▼

Mutation testing measures test suite effectiveness by intentionally injecting bugs into the code and verifying whether the existing tests catch those mutations. It evaluates test quality rather than code correctness.

Can I run mutation testing for different programming languages?▼

Yes, mutation testing supports multiple languages including JS/TS, Rust, Python, and Java/JVM. It utilizes various mutation testing tools like Stryker, cargo-mutants, mutmut, and Pitest to evaluate test suite effectiveness.

How do I prevent mutation testing from taking too long on a large codebase?▼

To control costs and execution time on large codebases, mutation testing can be scoped exclusively to High and Critical risk modules. This risk-based scoping ensures only the most crucial parts of the application are evaluated.

Can I use a mutation score threshold to control my build gates?▼

Yes, you can use mutation-score thresholds to control build gates. The mutation testing process evaluates your test suite effectiveness and uses the resulting score to determine if the build passes or fails.

What is the difference between mutation testing and traditional code coverage?▼

While traditional code coverage measures which lines of code are executed by tests, mutation testing injects bugs to check if those tests actually catch failures. This ensures your test suite effectiveness goes beyond mere execution.