mutation-test-runner

Mutation Test Runner - Auto-activating skill for Test Automation. Triggers on: mutation test runner, mutation test runner Part of the Test Automation skill category.

Install with Tessl CLI

npx tessl i github:jeremylongshore/claude-code-plugins-plus-skills --skill mutation-test-runner

What are skills?

1.02x

Quality

Does it follow best practices?

Impact

100%

1.02x

Average score across 3 eval scenarios

Optimize this skill with Tessl

npx tessl skill review --optimize ./planned-skills/generated/09-test-automation/mutation-test-runner/SKILL.md

SKILL.md

Review

Evals

Evaluation results

100%

JavaScript Library Quality Assessment

Jest mutation testing setup with Stryker

Criteria

Without context

With context

Uses Stryker core package

100%

Uses Jest runner plugin

100%

Stryker config file present

100%

Config specifies testRunner

100%

Config targets src files

100%

Mutation report produced

100%

Report includes mutation score

100%

Report lists surviving mutants

100%

node_modules removed

100%

package.json updated

100%

Step-by-step process

50%

100%

Without context: $0.3999 · 2m 11s · 26 turns · 27 in / 4,881 out tokens

With context: $0.4957 · 2m 7s · 28 turns · 28 in / 5,693 out tokens

100%

Python Service Test Coverage Audit

Python pytest mutation testing with mutmut

Criteria

Without context

With context

Uses mutmut or pytest-mutagen

100%

Runs against pytest

100%

Targets source module

100%

Mutation report produced

100%

Report includes mutation score

100%

Surviving mutants listed

100%

Tool version recorded

100%

No large cache files left

100%

Structured report sections

100%

Actionable recommendations

100%

Without context: $1.0385 · 4m 11s · 52 turns · 50 in / 11,524 out tokens

With context: $1.4751 · 4m 58s · 62 turns · 58 in / 16,226 out tokens

100%

Test Suite Hardening Based on Mutation Analysis

Mutation test results analysis and test improvement

Criteria

Without context

With context

analysis.md produced

100%

Summary table present

100%

All surviving mutants addressed

100%

Survival explanation provided

100%

Updated test file produced

100%

Boundary test for isReachable

100%

Tie-break test for selectFastestRoute

100%

estimateFuelCost variation test

100%

methodology.md produced

100%

Projected score improvement

100%

Step-by-step methodology

100%

Without context: $0.3929 · 2m 15s · 14 turns · 14 in / 7,648 out tokens

With context: $0.7778 · 3m 35s · 33 turns · 64 in / 11,475 out tokens

Evaluated: 5 days ago
Agent: Claude Code
Model: Claude Sonnet 4.6

Table of Contents

JavaScript Library Quality Assessment Python Service Test Coverage Audit Test Suite Hardening Based on Mutation Analysis

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.