Content
57%Weight 40%Scale 1-5Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
A highly actionable, code-first reference that is easy to follow and covers the Jest+TypeScript domain thoroughly. Its main weaknesses are two incorrect Jest config option names, no progressive disclosure (everything inlined in one large file), and several sections duplicating basic Jest knowledge Claude already has.
Suggestions
Fix the invalid Jest config options in jest.config.ts: "setupFilesAfterSetup" should be setupFilesAfterEnv, and "coverageThresholds" should be coverageThreshold — Jest will reject or ignore the current keys.
Split the SKILL.md into an overview plus reference files (e.g. references/msw.md, references/test-db.md, references/advanced-mocking.md) and link to them so the main file stays a lean overview.
Trim or move sections covering basic Jest knowledge Claude already has (jest.fn call counting, async rejects.toThrow, timer mocking basics) into an optional reference, keeping the core file focused on the skill's own conventions and configs.
Add an explicit validation step after scaffolding (e.g. "run npx jest once after config:init to confirm the setup executes") to give the workflow a concrete checkpoint.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The body is mostly code with lean prose, but several sections restate knowledge Claude already has — standalone jest.fn() call-count examples, async rejects.toThrow patterns, timer mocking, and basic snapshot testing are all standard Jest usage. It matches the 'mostly efficient but could be tightened' anchor rather than 2, since there is no padded explanatory prose. | 3 / 5 |
Actionability | Nearly all guidance is copy-paste executable: install commands, complete jest.config.ts variants, full spec files, and a command cheatsheet. However, the main config contains invalid Jest option names — "setupFilesAfterSetup" (should be setupFilesAfterEnv) and "coverageThresholds" (should be coverageThreshold) — which are minor but real gaps that prevent a 5. | 4 / 5 |
Workflow Clarity | A rough sequence exists (Prerequisites → Scaffold Command → Project Structure → config → test patterns → commands), but validation checkpoints are only implicit — there is no step verifying the scaffolded setup actually runs (e.g. 'run npx jest once after config to confirm') before writing tests. This matches the 'steps listed but checkpoints implicit' anchor. | 3 / 5 |
Progressive Disclosure | The single file is well-sectioned and easy to navigate, but ~450 lines are inlined monolithically with no bundle files at all — the MSW integration guide, test-database docker-compose setup, and many basic pattern examples clearly belong in separate reference files. This matches 'content that should be separate is inline' with good structure, i.e. the 3 anchor rather than 2 (which requires poor organization). | 3 / 5 |
Total | 13 / 20 Passed |