running-mutation-tests
tessl i github:jeremylongshore/claude-code-plugins-plus-skills --skill running-mutation-testsThis skill enables Claude to validate test suite quality by performing mutation testing. It is triggered when the user asks to run mutation tests, analyze test effectiveness, or improve test coverage. The skill introduces code mutations, runs tests against the mutated code, and reports on the "survival rate" of the mutations, indicating the effectiveness of the test suite. Use this skill when the user requests to assess the quality of their tests using mutation testing techniques. Specific trigger terms include "mutation testing", "test effectiveness", "mutation score", and "surviving mutants".
Validation
88%| Criteria | Description | Result |
|---|---|---|
metadata_version | 'metadata' field is not a dictionary | Warning |
license_field | 'license' field is missing | Warning |
Total | 14 / 16 Passed | |
Implementation
20%This skill content reads more like a conceptual explanation of mutation testing than actionable instructions for Claude. It lacks concrete commands, tool invocations, code examples, or specific guidance on how to actually perform mutation testing. The content explains what mutation testing is rather than how Claude should execute it.
Suggestions
Add concrete, executable commands or code showing how to run mutation testing (e.g., specific mutation testing tools like mutmut, cosmic-ray, or language-specific frameworks with actual CLI commands)
Replace the abstract 'How It Works' section with a step-by-step workflow including specific tool invocations and validation checkpoints
Transform the examples from descriptions of what 'the skill will do' into actual input/output examples with real commands and expected output formats
Remove explanatory content about what mutation testing is conceptually - Claude already knows this - and focus on project-specific configuration or tool usage
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The content is verbose and explains concepts Claude already knows (what mutation testing is, how it works conceptually). The 'How It Works' section describes basic mutation testing theory rather than providing actionable instructions. | 1 / 3 |
Actionability | No concrete code, commands, or executable guidance is provided. The examples describe what 'the skill will do' abstractly rather than showing actual commands, tool invocations, or code snippets Claude should use. | 1 / 3 |
Workflow Clarity | The 'How It Works' section lists steps but they are conceptual descriptions of mutation testing rather than actionable workflow steps. No validation checkpoints, specific tool commands, or error handling guidance is provided. | 2 / 3 |
Progressive Disclosure | Content is reasonably organized with clear sections, but everything is inline in one file. The 'Integration' section hints at connections to other tools but provides no concrete references or links to additional documentation. | 2 / 3 |
Total | 6 / 12 Passed |
Activation
100%This is a well-crafted skill description that excels across all dimensions. It provides specific concrete actions, includes explicit trigger guidance with natural keywords, and occupies a clear niche that distinguishes it from general testing skills. The description uses proper third-person voice throughout.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple concrete actions: 'introduces code mutations', 'runs tests against the mutated code', 'reports on the survival rate'. These are specific, actionable capabilities. | 3 / 3 |
Completeness | Clearly answers both what (validates test suite quality via mutation testing, introduces mutations, runs tests, reports survival rate) AND when (explicit 'Use this skill when...' clause plus specific trigger terms). | 3 / 3 |
Trigger Term Quality | Explicitly lists natural trigger terms: 'mutation testing', 'test effectiveness', 'mutation score', 'surviving mutants'. Also includes variations like 'run mutation tests' and 'analyze test effectiveness'. | 3 / 3 |
Distinctiveness Conflict Risk | Mutation testing is a distinct niche with specialized terminology ('mutation score', 'surviving mutants'). Unlikely to conflict with general testing or code quality skills due to specific domain focus. | 3 / 3 |
Total | 12 / 12 Passed |
Reviewed
Table of Contents
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