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perf-web-optimization

Optimize web performance: bundle size, images, caching, lazy loading, and overall page speed. Use when site is slow, reducing bundle size, fixing layout shifts, improving Time to Interactive, or optimizing for Lighthouse scores. Triggers on: web performance, bundle size, page speed, slow site, lazy loading. Do NOT use for Core Web Vitals-specific fixes (use core-web-vitals), running Lighthouse audits (use perf-lighthouse), or Astro-specific optimization (use perf-astro).

76

Quality

93%

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Passed

No known issues

SKILL.md
Quality
Evals
Security

Quality

Content

87%

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

This is a strong, well-structured performance optimization skill that provides concrete, actionable guidance across multiple optimization domains. Its main weakness is the lack of explicit verification/measurement steps after implementing optimizations—the stated workflow (Measure → Identify → Prioritize → Implement → Verify) isn't fully realized in the body content. The progressive disclosure is excellent, with appropriate delegation to reference files and related skills.

Suggestions

Add a 'Verify' section after implementation that shows how to confirm improvements (e.g., 'Run Lighthouse before and after, compare LCP/INP/CLS scores against the target metrics table above').

DimensionReasoningScore

Conciseness

The content is lean and efficient throughout. It jumps straight into actionable metrics, code examples, and checklists without explaining what web performance is or how browsers work. Every section earns its place with concrete, useful information.

3 / 3

Actionability

Provides fully executable HTML snippets, bash commands for bundle analysis, JavaScript code splitting patterns, and specific caching headers. The package replacement suggestions include concrete size comparisons. Everything is copy-paste ready.

3 / 3

Workflow Clarity

The opening states 'Measure → Identify → Prioritize → Implement → Verify' but the body doesn't follow this sequence with explicit validation checkpoints. There's no verification step after implementing optimizations (e.g., re-run Lighthouse, compare before/after metrics). The checklist helps but lacks a feedback loop for confirming improvements.

2 / 3

Progressive Disclosure

The skill provides a clear overview with well-organized sections, appropriately references the perf-lighthouse skill for audits, and points to three specific reference files for deeper content. References are one level deep and clearly signaled with descriptive labels.

3 / 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.

This is an excellent skill description that hits all the marks. It provides specific capabilities, rich natural trigger terms, explicit 'Use when' and 'Do NOT use' clauses, and clear boundaries against related skills. The negative trigger guidance is particularly strong for disambiguation in a skill set that likely contains multiple performance-related skills.

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions: bundle size optimization, image optimization, caching, lazy loading, and page speed improvement. These are clearly defined, actionable capabilities.

3 / 3

Completeness

Clearly answers both 'what' (optimize web performance across multiple dimensions) and 'when' (explicit 'Use when' clause with specific triggers, plus a 'Do NOT use' clause that further clarifies boundaries). This is exemplary completeness.

3 / 3

Trigger Term Quality

Excellent coverage of natural terms users would say: 'web performance', 'bundle size', 'page speed', 'slow site', 'lazy loading', 'layout shifts', 'Time to Interactive', 'Lighthouse scores'. These are all terms users would naturally use when seeking help.

3 / 3

Distinctiveness Conflict Risk

Exceptionally distinctive due to the explicit 'Do NOT use for' clause that delineates boundaries with related skills (core-web-vitals, perf-lighthouse, perf-astro). This proactively prevents conflicts with similar performance-related skills.

3 / 3

Total

12

/

12

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation11 / 11 Passed

Validation for skill structure

No warnings or errors.

Repository
tech-leads-club/agent-skills
Reviewed

Table of Contents

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If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.