jest-generator
Generate Jest unit tests for JavaScript/TypeScript with mocking, coverage. Use for JS/TS modules, React components, test generation, or encountering missing coverage, improper mocking, test structure errors.
85
82%
Does it follow best practices?
Impact
Pending
No eval scenarios have been run
Passed
No known issues
Quality
Discovery
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 a strong skill description that concisely covers specific capabilities (Jest test generation with mocking and coverage), uses natural trigger terms users would employ, and clearly delineates both what the skill does and when to use it. The description is well-scoped to a distinct domain and includes error-condition triggers (missing coverage, improper mocking) that add practical value.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple concrete actions and concepts: 'Generate Jest unit tests', 'mocking', 'coverage', and specifies targets like 'JS/TS modules' and 'React components'. These are specific, actionable capabilities. | 3 / 3 |
Completeness | Clearly answers both 'what' (generate Jest unit tests with mocking and coverage) and 'when' (for JS/TS modules, React components, test generation, missing coverage, improper mocking, test structure errors). The 'Use for...' clause serves as an explicit trigger guidance. | 3 / 3 |
Trigger Term Quality | Includes strong natural trigger terms users would say: 'Jest', 'unit tests', 'JavaScript', 'TypeScript', 'JS/TS', 'React components', 'mocking', 'coverage', 'test generation'. Good coverage of common variations. | 3 / 3 |
Distinctiveness Conflict Risk | Highly distinctive with a clear niche: Jest-specific testing for JavaScript/TypeScript. The combination of Jest, mocking, coverage, and React components creates a well-defined scope unlikely to conflict with other skills. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
64%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This is a solid, actionable skill with excellent executable code examples covering the major Jest patterns. Its main weaknesses are some redundancy (common matchers Claude already knows, repeated best practices), a missing explicit test-generation workflow with validation feedback loops (run tests → check results → fix → re-run), and all content being inline rather than using progressive disclosure for reference material.
Suggestions
Add an explicit step-by-step workflow for test generation: analyze source → identify exports → generate test file → run tests → check coverage → iterate on failures, with validation checkpoints after running tests.
Remove or significantly trim the 'Common Matchers' section since Claude already knows Jest's assertion API; keep only project-specific or unusual patterns.
Consolidate the 'Quality Checklist' and 'Best Practices' sections into one, removing duplication (e.g., 'organize with describe blocks' appears in both).
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The skill is mostly efficient but includes some content Claude already knows well, such as the common matchers reference section (toBe, toEqual, toBeTruthy, etc.) and basic Jest concepts. The 'Best Practices' section at the end largely repeats what's already demonstrated in the examples and checklist above it. | 2 / 3 |
Actionability | The skill provides fully executable, copy-paste ready code examples for every pattern: test structure, mocking, async testing, timers, React component testing, and running commands. All examples are concrete TypeScript with proper imports and realistic usage. | 3 / 3 |
Workflow Clarity | The skill provides a quality checklist and clear test structure, but lacks an explicit workflow sequence for generating tests (e.g., read source → identify exports → generate tests → run → check coverage → iterate). There's no validation/feedback loop for ensuring generated tests actually pass or meet coverage targets. | 2 / 3 |
Progressive Disclosure | The content is well-organized with clear section headers, but it's a monolithic file (~150 lines) where the common matchers reference and React component testing patterns could be split into separate reference files. No external file references are provided for deeper topics. | 2 / 3 |
Total | 9 / 12 Passed |
Validation
90%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 10 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
allowed_tools_field | 'allowed-tools' contains unusual tool name(s) | Warning |
Total | 10 / 11 Passed | |
- Repository
- secondsky/claude-skills
- Commit
88da5ff
- Reviewed
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