react-testing

React component testing with React Testing Library, Vitest/Jest, MSW for network mocking, accessibility assertions with axe, and the decision boundary between component tests and Playwright/Cypress end-to-end runs. Use when writing or fixing tests for React components, hooks, or pages.

Quality

96%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

92%

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

A comprehensive, highly actionable React testing reference with executable code and a clear TDD workflow. Its main weakness is progressive disclosure: everything lives inline in one large SKILL.md with no reference files to hold the deeper examples.

Suggestions

Move the longer, self-contained recipes (MSW setup block, coverage config, the Examples section) into reference files under references/ (e.g. references/msw-setup.md, references/coverage.md) and link to them from the body, keeping SKILL.md as a lean overview.

Add a one-line pointer near the top summarizing which reference file holds what, so each detailed topic is exactly one level deep and clearly signaled.

Confirm the cross-links to sibling skills (../accessibility/SKILL.md, ../e2e-testing/SKILL.md, ../../rules/react/testing.md) resolve to real files, since progressive disclosure scoring depends on referenced paths actually existing.

Dimension	Reasoning	Score
Conciseness	Largely lean reference-style content — terse bullets plus executable code, assuming Claude already knows React/testing basics — with minimal conceptual padding; not reduced to 2 because the orientation sections ('Core Principle', 'When to Activate') earn their place rather than restating common knowledge.	3 / 3
Actionability	Fully executable, copy-paste-ready code throughout (userEvent setup, MSW server handlers, renderHook, axe, vitest coverage config, test commands), matching the top anchor; not 2 because examples are complete rather than pseudocode.	3 / 3
Workflow Clarity	The TDD workflow gives a clear RED/GREEN/REFACTOR sequence with an explicit checkpoint ('Verify it fails for the right reason') and a feedback loop; testing is not destructive, so no cap applies, and the verify step lifts it above the 2 anchor.	3 / 3
Progressive Disclosure	Well-organized into clear sections and cross-links to sibling skills/rules are clearly signaled, but the skill is a single ~420-line monolith with full inline examples (MSW setup, coverage config, multiple full test cases) that could live in one-level-deep reference files; no bundle files exist to offload this detail, so it sits at the 2 anchor rather than 3.	2 / 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.

A strong, third-person description that states specific capabilities with named tools, gives an explicit 'Use when' trigger, and proactively distinguishes itself from adjacent E2E skills. No first/second-person voice or vague fluff is present.

Dimension	Reasoning	Score
Specificity	Enumerates multiple concrete capabilities with named tools — 'React Testing Library, Vitest/Jest, MSW for network mocking, accessibility assertions with axe' — matching the 'lists multiple specific concrete actions' anchor rather than merely naming a domain.	3 / 3
Completeness	Explicitly answers both what (component/hook/page testing with RTL, MSW, axe, E2E boundary) and when ('Use when writing or fixing tests for React components, hooks, or pages'), satisfying the top anchor; not capped at 2 because the 'Use when' clause is present.	3 / 3
Trigger Term Quality	Natural user phrasing ('writing or fixing tests', 'React components, hooks, or pages') plus the canonical tool names gives good coverage of terms a user would actually say; not reduced to 2 because common variations are well represented.	3 / 3
Distinctiveness Conflict Risk	Carves a clear React-testing niche and even names 'the decision boundary between component tests and Playwright/Cypress end-to-end runs', which actively disambiguates it from a sibling e2e-testing skill; unlikely to trigger for the wrong skill.	3 / 3
	Total	12 / 12 Passed

Validation

87%

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 — 14 / 16 Passed

Validation for skill structure

Criteria	Description	Result
metadata_version	'metadata.version' is missing	Warning
relative_links	Relative link issues: 7 suspicious	Warning

	Total	14 / 16 Passed

Repository: affaan-m/ECC
Path: skills/react-testing/SKILL.md
Commit: 0c1d7be

Reviewed: 2 days ago

Table of Contents

Discovery Implementation Validation

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