nw-mutation-test

Run feature-scoped mutation testing with cosmic-ray, PIT, or Stryker.

Updated Apr 15, 2026

Search Tags:#python #software-quality #test-automation #mutation-testing #config-generation #feature-testing

Ready to run

npx skills add https://github.com/StudentCristian/nWave-github --skill nw-mutation-test

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: nw-mutation-test
Source: https://github.com/StudentCristian/nWave-github/tree/main/.github/skills/nw-mutation-test
Command: npx skills add https://github.com/StudentCristian/nWave-github --skill nw-mutation-test

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) components.

What problem does it solve?

Mutation testing verifies that your test suite actually detects real bugs by measuring the kill rate of intentionally injected faults within the current feature's implementation.

Core Features & Use Cases

Feature-scoped mutation testing against implementation files for the current feature using language-appropriate tools (cosmic-ray for Python, PIT for Java, Stryker for JS/TS/C#).
Generates per-feature mutation configs (or uses a single config) and delegates execution to the software-crafter agent.
Produces a mutation-report.md at docs/feature/{feature-id}/deliver/mutation/ for analysis and traceability.

Quick Start

Run nw-mutation-test for a specific feature-id to initiate the mutation testing workflow and produce a mutation report.

Frequently Asked Questions about nw-mutation-test

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

FAQPage Schema

What is feature-scoped mutation testing and how does it measure test suite strength?▼

Feature-scoped mutation testing verifies your test suite's strength by injecting intentional faults into a feature's implementation files and measuring the kill rate of those mutations to see if your tests detect real bugs.

How do I run mutation testing for a specific feature in Python or JavaScript?▼

To run mutation testing for a feature, invoke the workflow with a feature-id. It supports Python via cosmic-ray, Java via PIT, and JavaScript, TypeScript, or C# via Stryker to generate per-feature mutation reports.

Does mutation testing work with Java and TypeScript codebases?▼

Yes, mutation testing supports Java codebases using PIT and JavaScript, TypeScript, or C# codebases using Stryker, applying language-appropriate tools to generate mutation reports for feature-based implementations.

What prerequisites are needed before running feature mutation testing?▼

Before running feature mutation testing, you need extracted implementation files, on-disk verification, language detection, and passing tests to satisfy pre-invocation checks for the selected feature.

Where does the mutation testing report get saved for feature traceability?▼

The mutation testing report is saved as a markdown file at docs/feature/{feature-id}/deliver/mutation/mutation-report.md, providing analysis and traceability for the evaluated feature's test suite.

What's the best way to validate that my Python tests actually detect real bugs?▼

The best way to validate that your Python tests detect real bugs is through mutation testing, which uses cosmic-ray to inject faults into your implementation files and measures whether your test suite catches them.