playground-msw-tests

REQUIRED and PRIMARY testing approach for packages/playground and packages/playground-ui. Triggers on: adding or modifying hooks, pages, route components, data-fetching code, React Query interactions, or any test work in these packages. Generates Vitest tests that drive the real @mastra/client-js + React Query stack through MSW handlers and typed fixtures derived from @mastra/client-js response types. This is the #1 way to test the playground packages — ABOVE Playwright E2E. Use Playwright only for cross-page user journeys that MSW cannot model.

Quality

90%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

88%Weight 40%Scale 1-5

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

The content is highly actionable with complete, copy-paste-ready skeletons and recipes, plus a clear priority order and verification checklist with validation checkpoints. It is efficient but slightly long, and provides no progressive disclosure via reference files despite its length.

Suggestions

Move the per-recipe examples (loading-state gate, feature-flag gating, vary-by-query-string) into a references/ file, keeping only the standard skeleton and fixture inline in SKILL.md, to improve progressive disclosure and reduce token load.

Trim rationale prose in the "What NOT to do" bullets (e.g., the className and implementation-mirror explanations) to one-line rules, since Claude can infer the why from the rule itself.

Consider extracting the full Standard Test Skeleton into a references/template.tsx file referenced from the body, leaving a condensed version inline.

Dimension	Reasoning	Score
Conciseness	The body is efficient and assumes Claude's competence (no explanations of what Vitest/MSW/React Query are), but contains minor instances of rationale-prose and is fairly long for a single approach, keeping it just below a clean lean-5.	4 / 5
Actionability	Provides fully copy-paste-ready code: a complete standard test skeleton, a complete fixture file, and multiple executable recipes (loading-state gate, enabled:false gating, feature-flag gating, vary-by-query-string) covering the common cases.	5 / 5
Workflow Clarity	A clear Priority Order sequence plus an explicit Verification Checklist with validation checkpoints (typecheck passes, runs in isolation, no onUnhandledRequest failures, coverage target) and a feedback loop via loud unhandled-request failures.	5 / 5
Progressive Disclosure	Well-organized into clearly labeled sections, but the skill is ~265 lines with no bundle files or any external references, so it does not qualify for the simple-skill 5 exception and inlines recipes/skeletons that could be referenced out.	4 / 5
	Total	18 / 20 Passed

Description

92%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description is specific, well-scoped, and explicitly answers both what it does and when to use it via a concrete "Triggers on:" clause. Trigger-term coverage is strong but slightly technical rather than synonym-broad, capping that one dimension at 4.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — "Generates Vitest tests that drive the real @mastra/client-js + React Query stack through MSW handlers and typed fixtures derived from @mastra/client-js response types" — giving comprehensive coverage of the testing domain rather than just a few actions.	5 / 5
Completeness	Explicitly answers both what ("Generates Vitest tests that drive the real @mastra/client-js + React Query stack through MSW handlers...") and when (an explicit "Triggers on:" clause with concrete trigger phrases), satisfying the top anchor.	5 / 5
Trigger Term Quality	Natural developer-facing triggers are present ("adding or modifying hooks, pages, route components, data-fetching code, React Query interactions, or any test work"), but coverage leans technical and lacks the synonym/file-extension breadth that would make it comprehensive.	4 / 5
Distinctiveness Conflict Risk	Scoped to two named packages, cites a specific SDK and stack, and explicitly differentiates from Playwright E2E ("ABOVE Playwright E2E. Use Playwright only for cross-page user journeys"), giving a clear niche with minimal conflict risk.	5 / 5
	Total	19 / 20 Passed

Validation

100%

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 — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: mastra-ai/mastra
Path: .claude/skills/playground-msw-tests/SKILL.md
Commit: d6ce34a

Reviewed: about 17 hours ago

Table of Contents

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