javascript-testing-patterns

Implement comprehensive testing strategies using Jest, Vitest, and Testing Library for unit tests, integration tests, and end-to-end testing with mocking, fixtures, and test-driven development. Use when writing JavaScript/TypeScript tests, setting up test infrastructure, or implementing TDD/BDD workflows.

Quality

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Does it follow best practices?

Impact

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No eval scenarios have been run

Securityby

Passed

No known issues

Quality

Content

72%

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

A well-structured, highly actionable testing reference with clean progressive disclosure into a real bundle file. Its main weakness is token weight: several inline example suites are reference-grade material that could be condensed or offloaded.

Suggestions

Condense or move the most boilerplate example suites (e.g. the UserService and EmailService tests) into references/advanced-testing-patterns.md, keeping only one minimal illustrative unit-test pattern inline.

For the integration-testing flow, add an explicit validate/checkpoint sequence (e.g. truncate → run → assert → tear down) rather than leaving it as a single prose sentence.

Trim the flat 15-item Best Practices list to the highest-value rules, or relocate the rest to a reference, to tighten token usage.

Dimension	Reasoning	Score
Conciseness	The body is mostly efficient and free of beginner-concept filler, but several full inline test suites (calculator, UserService, EmailService) are textbook patterns Claude already knows and could be condensed or pushed to references.	2 / 3
Actionability	Provides fully executable, copy-paste-ready configuration (jest.config.ts, vitest.config.ts) and complete test patterns including a working faker fixture with overrides.	3 / 3
Workflow Clarity	Sections are well-organized with a clear "When to Use" list, but there is no explicit validation/feedback-loop sequencing for the riskier flows (e.g. integration tests), so checkpoints remain implicit.	2 / 3
Progressive Disclosure	Keeps the core overview inline and routes advanced material (API integration tests, React renderHook, snapshots, timers) to a single one-level-deep reference that is clearly signaled with repeated markdown links.	3 / 3
	Total	10 / 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.

A strong, third-person description that names concrete capabilities, explicit trigger terms, and a clear use-when clause. It cleanly answers both what the skill does and when to apply it.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — "unit tests, integration tests, and end-to-end testing with mocking, fixtures, and test-driven development" — rather than vague abstractions.	3 / 3
Completeness	Explicitly states both what it does and when to invoke it via the "Use when writing JavaScript/TypeScript tests, setting up test infrastructure, or implementing TDD/BDD workflows" clause.	3 / 3
Trigger Term Quality	Covers natural user-facing terms ("JavaScript/TypeScript tests", "test infrastructure", "TDD/BDD workflows") alongside recognizable framework names (Jest, Vitest, Testing Library).	3 / 3
Distinctiveness Conflict Risk	Scoped to JS/TS testing with specific named frameworks and workflows, giving it a clear niche unlikely to trigger for unrelated skills.	3 / 3
	Total	12 / 12 Passed

Validation

93%

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 — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
skill_md_line_count	SKILL.md is long (538 lines); consider splitting into references/ and linking	Warning

	Total	15 / 16 Passed

Repository: wshobson/agents
Commit: 5cc2549

Reviewed: 5 days ago

Table of Contents

Discovery Implementation Validation

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