Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/ArabelaTso/Skills-4-SEnpx agentmods add skills/arabelatso/skills-4-se/mutation-test-suite-optimizerWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/arabelatso/skills-4-se/mutation-test-suite-optimizer)<a href="https://agentmods.dev/skills/arabelatso/skills-4-se/mutation-test-suite-optimizer"><img src="https://agentmods.dev/badge/skills/arabelatso/skills-4-se/mutation-test-suite-optimizer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/arabelatso/skills-4-se/mutation-test-suite-optimizer"><img src="https://agentmods.dev/badge/skills/arabelatso/skills-4-se/mutation-test-suite-optimizer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00101 | $0.00620 |
| Opus 5 | $0.00051 | $0.00310 |
| Sonnet 5 | $0.00020 | $0.00124 |
| Haiku 4.5 | $0.00010 | $0.00062 |
Grade A, and why
mutation-test-suite-optimizer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mutation Test Suite Optimizer
Overview
This skill optimizes test suites using mutation testing, selecting a minimal subset of tests that maximizes mutation kill rate while reducing execution time and redundancy.
Quick Start
# Optimize test suite with mutation testing
python scripts/optimize.py /path/to/repo --tests tests/
# Use specific mutation operators
python scripts/optimize.py repo/ --tests tests/ --operators AOR,ROR,COR
# Generate optimization report
python scripts/optimize.py repo/ --tests tests/ --output report.json
What Gets Optimized
- Test Selection - Identify minimal test subset for maximum coverage
- Redundancy Removal - Eliminate tests that kill same mutants
- Mutation Coverage - Maximize mutants killed
- Execution Time - Reduce overall test execution time
- Test Quality - Identify weak or ineffective tests
Mutation Operators
Supports common mutation operators:
- AOR - Arithmetic Operator Replacement
- ROR - Relational Operator Replacement
- COR - Conditional Operator Replacement
- SOR - Shift Operator Replacement
- LOR - Logical Operator Replacement
- ASR - Assignment Operator Replacement
Optimization Report
Generates detailed report with:
- Optimized Test Suite - Minimal test subset
- Mutation Kill Rate - Percentage of mutants killed
- Killed Mutants - List of detected mutants
- Surviving Mutants - Mutants that escaped detection
- Redundant Tests - Tests that can be removed
- Execution Time Savings - Time reduction achieved
Example report:
{
"original_tests": 150,
"optimized_tests": 45,
"mutation_kill_rate": 92.5,
"killed_mutants": 185,
"surviving_mutants": 15,
"time_savings": "67%"
}
Usage
python scripts/optimize.py <repo_path> --tests <test_dir> [--operators <ops>] [--output <report.json>]
Tips
- Run regularly to maintain test suite quality
- Focus on high-value tests that kill unique mutants
- Remove redundant tests to speed up CI/CD
- Use surviving mutants to guide new test creation
- Balance mutation score with execution time
- Integrate into continuous testing pipeline
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 9d ago First seen · 79 lines · 101 tokens per session scan A 0f144496e212
mutation-test-suite-optimizer is a skill published in the GitHub repository ArabelaTso/Skills-4-SE (252 stars, last pushed 22d ago), licensed Apache-2.0. It adds 101 tokens to every session and 620 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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