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web-performance-optimization

Optimize website and web application performance including loading speed, Core Web Vitals, bundle size, caching strategies, and runtime performance

56

Quality

64%

Does it follow best practices?

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Adds up to 20 points to the overall score

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SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./plugins/AI-Agents-Safe-Coding-Skills-claude/skills/web-performance-optimization/SKILL.md

The canonical home for this skill is web-performance-optimization in administrakt0r/AI-Agents-Safe-Coding-Skills

SKILL.md
Quality
Evals
Security

Quality

Content

63%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 executable examples and a clear sequenced workflow, but it is over-long and padded with restated knowledge, and it is monolithic with no reference files for a skill of this size.

Suggestions

Move the Best Practices, Common Pitfalls, Performance Tools, and Additional Resources sections into separate reference files (e.g. references/best-practices.md, references/tools.md) and link to them from SKILL.md.

Trim truisms Claude already knows ('Measure First', 'Don't Optimize Blindly', tool descriptions) to reduce token cost.

Strengthen the Verify step into an explicit feedback loop: re-measure, compare against the baseline, and revert/retry if a metric regresses.

DimensionReasoningScore

Conciseness

At ~640 lines, the body is noticeably verbose with several padded sections (Best Practices, Common Pitfalls, Performance Tools, Additional Resources) that restate knowledge Claude already has, alongside genuinely useful code examples.

2 / 5

Actionability

Provides fully executable, copy-paste-ready HTML/JS/CSS/bash covering the three common cases (Core Web Vitals fixes, bundle-size reduction, image optimization) with concrete before/after code.

5 / 5

Workflow Clarity

A clear five-step sequence (Measure, Identify, Prioritize, Implement, Verify) with a verification checkpoint in Step 5, though the feedback loop is light (no explicit 'if metrics regress, revert and retry').

4 / 5

Progressive Disclosure

No bundle files exist and all content is inlined in a single 640-line SKILL.md; section headers give structure, but examples, tools, and checklists that belong in separate reference files are not split out.

3 / 5

Total

14

/

20

Passed

Description

66%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 clearly conveys the domain and lists several specific capability areas, but it lacks an explicit 'when to use' trigger clause, which caps completeness. Trigger terms are good but could add common synonyms like Lighthouse or LCP.

Suggestions

Add an explicit 'Use when...' clause stating when Claude should invoke this skill (e.g. 'Use when the user reports slow loading, asks to improve Core Web Vitals, or wants to reduce bundle size').

Include more natural synonyms and tool names users say (Lighthouse, PageSpeed, LCP, TTI) to broaden trigger coverage.

Reframe capability topics as concrete actions (e.g. 'Measures and improves loading speed...') to sharpen specificity.

DimensionReasoningScore

Specificity

Names the domain and several concrete capability areas ('loading speed, Core Web Vitals, bundle size, caching strategies, and runtime performance'), though these are topics rather than discrete verb-actions like 'extract' or 'fill'.

4 / 5

Completeness

The 'what' is clear ('Optimize website and web application performance including...'), but there is no explicit 'Use when...' trigger clause, so completeness is capped at 3 per the guidelines.

3 / 5

Trigger Term Quality

Includes natural terms users say ('website', 'web application', 'performance', 'Core Web Vitals', 'bundle size', 'caching'), but omits common synonyms like 'PageSpeed', 'Lighthouse', or 'LCP'.

4 / 5

Distinctiveness Conflict Risk

The web-performance niche with Core Web Vitals and bundle-size triggers is mostly distinct, with only minor overlap risk against general frontend-best-practices skills.

4 / 5

Total

15

/

20

Passed

Validation

87%

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

Validation14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

skill_md_line_count

SKILL.md is long (650 lines); consider splitting into references/ and linking

Warning

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

14

/

16

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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