mutation-test-suite-optimizer

Optimize test suites using mutation testing to maximize mutation kill rate with minimal tests. Use when you need to reduce test suite size while maintaining quality, identify redundant tests, improve mutation coverage, or validate test effectiveness. The skill analyzes test coverage, execution intervals, and redundancy using mutation operators, selects or generates a minimal subset of tests that maximizes mutation kill rate, and outputs an optimized test suite with detailed reports showing killed and surviving mutants. Supports multiple programming languages and mutation testing frameworks.

Install with Tessl CLI

npx tessl i github:ArabelaTso/Skills-4-SE --skill mutation-test-suite-optimizer

What are skills?

Review — 76%

Does it follow best practices?

If you maintain this skill, you can automatically optimize it using the tessl CLI to improve its score:

npx tessl skill review --optimize ./path/to/skill

Learn more

Validation — 11 / 11 Passed

Validation for skill structure

SKILL.md

Review

Evals

Evaluation results

100%

63%

Optimize a Bloated Python Test Suite

Mutation test suite optimization workflow

Criteria

Without context

With context

Uses optimize.py script

100%

Correct repo and test args

100%

Uses --operators flag

100%

Uses --output flag

100%

Report has original_tests field

25%

100%

Report has optimized_tests field

25%

100%

Report has mutation_kill_rate field

25%

100%

Report has killed_mutants field

28%

100%

Report has surviving_mutants field

100%

Report has time_savings field

28%

100%

Redundant tests identified

100%

High-value tests retained

100%

Without context: $0.9923 · 5m 45s · 32 turns · 38 in / 16,381 out tokens

With context: $1.0403 · 7m 59s · 34 turns · 101 in / 15,875 out tokens

100%

38%

Improve Test Coverage for a Data Validation Library

Surviving mutants guiding new tests

Criteria

Without context

With context

Uses optimize.py script

90%

100%

Produces report.json

87%

100%

Report has surviving_mutants

37%

100%

Report has killed_mutants

100%

Report has mutation_kill_rate

14%

100%

Report has original_tests and optimized_tests

100%

Report has time_savings

100%

Uses --operators flag

100%

New tests derived from surviving mutants

100%

Surviving mutant rationale documented

100%

Kill rate improves after new tests

100%

Mutation operators applied

62%

100%

Without context: $2.7778 · 10m 29s · 69 turns · 73 in / 28,681 out tokens

With context: $3.0294 · 11m 55s · 81 turns · 240 in / 32,563 out tokens

100%

45%

Speed Up CI/CD by Integrating Mutation-Based Test Optimization

CI/CD pipeline integration

Criteria

Without context

With context

Uses optimize.py script

90%

100%

Uses --tests argument

100%

Uses --operators flag

100%

Uses --output flag

100%

Report has all required fields

20%

100%

Redundant tests removed

90%

100%

Pipeline runs optimized suite

100%

Execution time improvement shown

50%

100%

Balances score and time

87%

100%

Periodic re-optimization configured

100%

Pipeline is self-contained

85%

100%

High-value tests prioritized

40%

100%

Without context: $3.7970 · 14m 29s · 86 turns · 92 in / 40,364 out tokens

With context: $1.5476 · 6m 28s · 47 turns · 310 in / 21,670 out tokens

Evaluated: about 18 hours ago
Agent: Claude Code

Table of Contents

Optimize a Bloated Python Test Suite Improve Test Coverage for a Data Validation Library Speed Up CI/CD by Integrating Mutation-Based Test Optimization

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.