react-best-practices

Comprehensive performance optimization guide for React and Next.js applications, maintained by Vercel. Use when writing new React components or Next.js pages, implementing data fetching (client or server-side), or reviewing code for performance issues.

Quality

48%

Does it follow best practices?

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tessl review fix ./skills/react-best-practices/SKILL.md

Quality

Content

36%Scale 1-5

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

This skill functions primarily as a table of contents or index for 45 performance optimization rules, but provides almost no actionable content itself. It lacks executable code examples, concrete workflows, and validation steps. While the categorization and prioritization are useful organizational elements, the skill body alone does not enable Claude to perform any of the described tasks without accessing the referenced (but unverified) external files.

Suggestions

Add at least one concrete, executable code example for the highest-priority categories (e.g., show a before/after for async-parallel with Promise.all()) so the skill is actionable even without bundle files.

Define a workflow for the 'reviewing code for performance issues' use case, e.g., a checklist that walks through categories in priority order with specific validation steps.

Remove the duplicate 'When to Use' section at the bottom and the repeated description from the opening paragraph to improve conciseness.

For each category in the quick reference, include at least one inline mini-example or pattern snippet rather than deferring everything to external files.

Dimension	Reasoning	Score
Conciseness	The content is mostly a reference table/index, which is reasonably efficient, but includes some redundancy (duplicate 'When to Use' sections, the description is repeated from frontmatter, and the closing 'When to Use' adds nothing). The category table and quick reference lists are useful but could be tighter.	3 / 5
Actionability	The skill provides no executable code, no concrete examples, and no specific commands. It is essentially an index/catalog of rule names with brief one-line descriptions. All actual guidance is deferred to external rule files. A developer or Claude reading only this file would not know how to implement any of the 45 rules.	2 / 5
Workflow Clarity	There is no workflow, sequence, or process described. The 'How to Use' section simply says to read individual rule files. There are no validation steps, no decision points, and no guidance on how to apply rules in sequence or combination. For a skill that covers 'reviewing code for performance issues' and 'refactoring,' the absence of any workflow is a significant gap.	2 / 5
Progressive Disclosure	The skill attempts progressive disclosure by referencing individual rule files (rules/async-parallel.md, etc.) and a compiled AGENTS.md. However, no bundle files are provided, so we cannot verify these references exist. The structure is reasonable as an overview pointing to details, but the references are not clearly signaled per-rule (only three example paths are shown), and the inline content is essentially just a list without enough context to be useful on its own.	3 / 5
	Total	10 / 20 Passed

Description

61%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 establishes a clear domain (React/Next.js performance optimization) and includes an explicit 'Use when' clause with multiple trigger scenarios, which is good. However, it lacks specificity about what concrete optimizations or techniques the skill covers — calling it a 'guide' without listing specific capabilities (e.g., memoization strategies, bundle splitting, image optimization) makes it hard to distinguish from general React/Next.js skills. The trigger conditions are also overly broad, potentially causing this skill to activate for any React/Next.js work.

Suggestions

Add specific optimization techniques the skill covers, e.g., 'Covers memoization with useMemo/useCallback, code splitting, lazy loading, image optimization, and server component patterns'

Narrow the 'Use when' triggers to focus on performance-specific scenarios, e.g., 'Use when the user mentions slow rendering, bundle size reduction, load time optimization, or asks to optimize existing React/Next.js code' rather than broadly triggering on all component writing

Dimension	Reasoning	Score
Specificity	The description names the domain (React/Next.js performance optimization) but actions are minimal and generic — 'writing new React components', 'implementing data fetching', and 'reviewing code for performance issues' are broad activity categories rather than concrete actions the skill performs. It says it's a 'guide' but doesn't specify what concrete optimizations or techniques it covers.	2 / 5
Completeness	Has both 'what' (performance optimization guide for React/Next.js) and 'when' (writing components, implementing data fetching, reviewing code for performance). The 'what' is somewhat vague — it's described as a 'guide' without specifying what concrete guidance it provides. The 'when' clause is explicit with a 'Use when' structure and multiple trigger scenarios.	4 / 5
Trigger Term Quality	Includes good natural keywords like 'React', 'Next.js', 'components', 'data fetching', 'client or server-side', 'performance issues', and 'Vercel'. Missing some common synonyms and terms users might say like 'slow rendering', 'bundle size', 'lazy loading', 'memoization', 'SSR', 'SSG', or 'hydration'.	4 / 5
Distinctiveness Conflict Risk	While it specifies React/Next.js performance optimization, the broad scope ('writing new React components', 'implementing data fetching', 'reviewing code') could overlap significantly with general React development skills, Next.js skills, or code review skills. The performance optimization angle provides some distinction but the trigger conditions are very broad.	3 / 5
	Total	13 / 20 Passed

Validation

90%

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 — 10 / 11 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	10 / 11 Passed

Repository: administrakt0r/AI-Agents-Safe-Coding-Skills
Path: skills/react-best-practices/SKILL.md
Commit: 57c135b

Reviewed: 2 days ago

Table of Contents

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