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webp-format

Use when reviewing image assets, markup, and CDN or build transforms related to Use WebP format with fallbacks. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.

65

Quality

78%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./skills/webp-format/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

57%

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

The body is well-structured as a progressive-disclosure overview with a valid single reference, but its inline Check/Fix/Explain guidance is vague and concept-explaining rather than actionable, with no explicit verification checkpoint.

Suggestions

Tighten the intro and Check/Fix/Explain sections: drop the 'WebP is smaller than JPEG/PNG' concept explanation and replace abstract lines with a concrete pointer or a minimal code snippet.

Add an explicit verification step in the workflow (e.g., 'Confirm in DevTools Network tab that image/webp is served and the fallback loads in Safari <14') so the sequence has a real checkpoint.

Either inline one small executable example (a picture/source snippet) in the body or make the Code Review section prescriptive about which files/attributes to inspect so it reads as instruction rather than description.

DimensionReasoningScore

Conciseness

The body is mostly lean, but the intro line 'WebP is smaller than JPEG and PNG at similar quality—using it reduces page weight by 25-35%' explains a concept Claude already knows, and the Check/Fix/Explain sections ('Convert images to WebP format and implement proper fallback strategies') are padded restatements that could be tightened.

2 / 3

Actionability

The Code Review section gives some concrete direction ('Flag exact files or components where format choice, sizing, or loading behavior violates the rule, and describe how to confirm the fix in DevTools'), but Check/Fix/Explain are abstract with no executable code or commands in the body — all runnable content is deferred to rule.md.

2 / 3

Workflow Clarity

Check/Fix/Explain/Code Review sections are listed but not framed as an explicit sequence, and validation is only implicit (the DevTools mention) rather than a stated checkpoint, so it sits at the 'sequence present but checkpoints missing' level.

2 / 3

Progressive Disclosure

The body is a clean overview with well-organized sections and a single clearly signaled one-level-deep reference — 'see references/rule.md' — and that file exists, matching the top anchor.

3 / 3

Total

9

/

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.

The description is specific, trigger-rich, and clearly distinguishes both the capability and the use condition in third-person imperative form. It is among the strongest descriptions in the reference set.

DimensionReasoningScore

Specificity

It lists multiple concrete actions — 'reviewing image assets, markup, and CDN or build transforms' and 'Check encoded size, rendered size, loading strategy, and above-the-fold impact together' — matching the anchor for several specific concrete actions.

3 / 3

Completeness

It explicitly answers both what (reviewing assets/markup/transforms, checking sizes/loading/impact) and when via the explicit 'Use when reviewing...' trigger clause, matching the top anchor.

3 / 3

Trigger Term Quality

Natural frontend terms a user would say appear throughout — 'image assets, markup', 'CDN or build transforms', 'WebP format with fallbacks', 'above-the-fold impact' — giving good coverage rather than jargon-only or generic phrasing.

3 / 3

Distinctiveness Conflict Risk

The narrow scope 'related to Use WebP format with fallbacks' carves a clear niche with distinct triggers, making it unlikely to fire for unrelated image or build skills.

3 / 3

Total

12

/

12

Passed

Validation

93%

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

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

Total

15

/

16

Passed

Repository
thedaviddias/Front-End-Checklist
Reviewed

Table of Contents

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