react-performance

React and Next.js performance optimization patterns adapted from Vercel Engineering's React Best Practices (https://github.com/vercel-labs/agent-skills). Organizes 70+ rules across 8 priority categories — waterfalls, bundle size, server-side, client fetching, re-render, rendering, JS micro-perf, advanced. Use when writing, reviewing, or refactoring React/Next.js code for performance.

Quality

81%

Does it follow best practices?

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Securityby

Passed

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Quality

Content

78%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 body is highly actionable with concrete code examples and clear prioritization via the priority index and Lighthouse mapping. Main weaknesses are progressive disclosure (everything inlined in one large file) and minor conciseness padding in the intro.

Suggestions

Split the 8 category sections into per-category reference files (e.g., references/waterfalls.md) and keep SKILL.md as an overview with the priority index pointing to them.

Trim the opening paragraph that repeats the frontmatter description.

Add a short review workflow ('1. identify symptom -> 2. consult Lighthouse mapping -> 3. apply matching rule -> 4. re-check metric') with a validation step.

Dimension	Reasoning	Score
Conciseness	Mostly lean code examples with brief explanations and INCORRECT/CORRECT contrasts; the opening paragraph repeats the frontmatter description and a few explanatory sentences could be trimmed.	4 / 5
Actionability	Extensive copy-paste-ready TypeScript/TSX examples with explicit INCORRECT vs CORRECT pairs covering the common cases across all 8 categories.	5 / 5
Workflow Clarity	The Priority Index table and Lighthouse/Web Vitals mapping provide clear prioritized sequencing and decision guidance; no explicit validation checkpoints, but the skill is review-oriented rather than destructive.	4 / 5
Progressive Disclosure	All 70+ rules are inlined in a single 570-line file with no external reference files; it is well-structured with a navigable priority index, but SKILL.md serves as the full catalog rather than an overview pointing to detailed materials.	3 / 5
	Total	16 / 20 Passed

Description

83%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 strong: it answers both 'what' and 'when' explicitly, names a clear niche, and enumerates 8 specific priority categories. Trigger terms are natural but could add common synonyms (slow, Lighthouse, Core Web Vitals).

Dimension	Reasoning	Score
Specificity	Lists 8 named priority categories (waterfalls, bundle size, server-side, client fetching, re-render, rendering, JS micro-perf, advanced) giving concrete coverage, though the action framing ('optimization patterns', 'organizes rules') is somewhat abstract rather than discrete verbs.	4 / 5
Completeness	Explicitly answers both what ('Organizes 70+ rules across 8 priority categories') and when ('Use when writing, reviewing, or refactoring...') with concrete trigger phrases.	5 / 5
Trigger Term Quality	'Use when writing, reviewing, or refactoring React/Next.js code for performance' uses natural trigger phrases users would say; missing some common synonyms like 'slow', 'Lighthouse', or 'Core Web Vitals'.	4 / 5
Distinctiveness Conflict Risk	Clearly a React/Next.js performance niche with distinct triggers and minimal conflict risk; minor overlap with sibling skills like react-patterns and frontend-patterns noted in the Related section.	4 / 5
	Total	17 / 20 Passed

Validation

81%

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 — 13 / 16 Passed

Validation for skill structure

Criteria	Description	Result
skill_md_line_count	SKILL.md is long (576 lines); consider splitting into references/ and linking	Warning
metadata_version	'metadata.version' is missing	Warning
relative_links	Relative link issues: 6 suspicious	Warning

	Total	13 / 16 Passed

Repository: affaan-m/ECC
Path: skills/react-performance/SKILL.md
Commit: d8409a4

Reviewed: 1 day ago

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