behavioral-mutation-analyzer

Analyzes surviving mutants from mutation testing to identify why tests failed to detect them. Takes repository code, test suite, and mutation testing results as input. Identifies root causes including insufficient coverage, equivalent mutants, weak assertions, and missed edge cases. Automatically generates actionable test improvements and new test cases. Use when analyzing mutation testing results, improving test suite effectiveness, investigating low mutation scores, generating tests to kill surviving mutants, or enhancing test quality based on mutation analysis.

Quality

92%

Does it follow best practices?

Impact

—

No eval scenarios have been run

Securityby

Passed

No known issues

Quality

Content

85%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This is a well-structured, highly actionable skill for mutation testing analysis. Its strengths are the clear 6-step workflow with validation checkpoints, concrete code examples across multiple languages, and appropriate progressive disclosure to reference files. The main weakness is moderate verbosity in explanatory sections that could be trimmed given Claude's existing knowledge of testing concepts.

Suggestions

Trim the category explanations (e.g., 'Insufficient Coverage', 'Equivalent Mutants') to focus on indicators and examples rather than explaining what each concept means

Remove the 'Mutation Operators Reference' section or move it entirely to the referenced mutation_operators.md file to reduce inline content

Dimension	Reasoning	Score
Conciseness	The skill is reasonably efficient but includes some unnecessary explanation (e.g., the overview section restates what mutation testing is, and some categories have verbose explanations). The content could be tightened by removing redundant descriptions and trusting Claude's understanding of mutation testing concepts.	2 / 3
Actionability	Provides concrete, executable code examples across multiple languages (Java, Python, JavaScript), specific tool commands for PIT/Stryker/mutmut, and copy-paste ready test generation examples. Each category includes clear indicators and actionable analysis steps.	3 / 3
Workflow Clarity	Clear 6-step workflow with explicit validation checklist in Step 1, well-sequenced analysis process, and clear decision points for test generation strategies. The workflow includes feedback loops (iterative improvement section) and explicit checkpoints throughout.	3 / 3
Progressive Disclosure	Well-structured with clear overview, appropriately detailed inline content for core workflow, and one-level-deep references to external files (mutation_operators.md, tool_integration.md, test_patterns.md, report template). Navigation is clear and content is appropriately split.	3 / 3
	Total	11 / 12 Passed

Description

100%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

This is an excellent skill description that clearly defines a specialized niche in mutation testing analysis. It provides comprehensive coverage of capabilities, inputs, outputs, and explicit trigger conditions. The description uses appropriate third-person voice and domain-specific terminology that users in this space would naturally employ.

Dimension	Reasoning	Score
Specificity	Lists multiple specific concrete actions: 'Analyzes surviving mutants', 'Takes repository code, test suite, and mutation testing results as input', 'Identifies root causes including insufficient coverage, equivalent mutants, weak assertions, and missed edge cases', 'generates actionable test improvements and new test cases'.	3 / 3
Completeness	Clearly answers both what (analyzes mutants, identifies root causes, generates test improvements) AND when with explicit 'Use when...' clause covering multiple trigger scenarios: 'analyzing mutation testing results, improving test suite effectiveness, investigating low mutation scores, generating tests to kill surviving mutants'.	3 / 3
Trigger Term Quality	Includes natural keywords users would say: 'mutation testing', 'surviving mutants', 'mutation scores', 'test suite', 'kill surviving mutants', 'test quality'. These are domain-appropriate terms that users working with mutation testing would naturally use.	3 / 3
Distinctiveness Conflict Risk	Highly distinctive niche focused specifically on mutation testing analysis. The specialized terminology ('surviving mutants', 'mutation scores', 'kill surviving mutants') creates clear boundaries that would not conflict with general testing or code analysis skills.	3 / 3
	Total	12 / 12 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 11 / 11 Passed

Validation for skill structure

No warnings or errors.

Repository: ArabelaTso/Skills-4-SE
Commit: 0f00a4f

Reviewed: 4 months ago

Table of Contents

Discovery Implementation Validation

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