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.
68
82%
Does it follow best practices?
Impact
—
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 unit test generation with mocking and coverage), targets (JS/TS modules, React components), and explicit trigger conditions (missing coverage, improper mocking, test structure errors). It uses proper third-person voice and includes natural keywords users would employ. The description is well-structured and distinctive enough to avoid conflicts with other skills.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple concrete actions and domains: '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' (Use for JS/TS modules, React components, test generation, missing coverage, improper mocking, test structure errors). Explicit trigger guidance is present. | 3 / 3 |
Trigger Term Quality | Includes strong natural keywords users would say: 'Jest', 'unit tests', 'JavaScript', 'TypeScript', 'JS/TS', 'React components', 'mocking', 'coverage', 'test generation'. Good coverage of common variations and terms. | 3 / 3 |
Distinctiveness Conflict Risk | Highly specific niche: Jest testing for JavaScript/TypeScript. The combination of 'Jest', 'unit tests', 'mocking', 'coverage', and 'React components' creates a distinct trigger profile 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 reference-style skill with excellent executable code examples covering the major Jest patterns. Its main weaknesses are the lack of an explicit test-generation workflow with validation steps (run tests, check coverage, iterate) and some redundancy in the matchers/best practices sections that Claude already knows. Trimming known concepts and adding a clear step-by-step generation workflow would significantly improve it.
Suggestions
Add an explicit step-by-step workflow for test generation: analyze source → identify exports/edge cases → generate test file → run tests → verify passing → check coverage → iterate on gaps.
Remove or significantly trim the 'Common Matchers' section, as these are standard Jest API knowledge Claude already has.
Consolidate the 'Quality Checklist' and 'Best Practices' sections into a single concise checklist to eliminate overlap.
Add a validation feedback loop: after generating tests, run them and verify they pass before considering the task complete.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The skill is mostly efficient but includes some unnecessary content Claude already knows, such as the common matchers reference section (toBe, toEqual, toBeTruthy, etc.) and the best practices list which largely restates general testing knowledge. The quality checklist and best practices sections overlap significantly. | 2 / 3 |
Actionability | The skill provides fully executable, copy-paste ready code examples for test structure, mocking, async testing, timers, React component testing, and running tests. All code blocks are concrete TypeScript with real patterns rather than pseudocode. | 3 / 3 |
Workflow Clarity | The skill provides clear patterns and a quality checklist, but lacks an explicit workflow sequence for generating tests (e.g., read source → identify exports → generate test file → run tests → check coverage → fix gaps). 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 with no references to external files. The common matchers section and React testing section could be split into separate reference files to keep the main skill leaner, especially given there are no bundle files. | 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
5e92b71
- Reviewed
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