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optimized

Use when reviewing image assets, markup, and CDN or build transforms related to Optimise images for faster loading. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.

70

Quality

86%

Does it follow best practices?

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SKILL.md
Quality
Evals
Security

Quality

Content

72%

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

The content is actionable and well-structured with a clean single-level reference, but it spends tokens explaining compression fundamentals Claude already knows and omits an explicit validation/verification checkpoint for the batch re-encoding workflow it prescribes.

Suggestions

Trim the intro and "Explain" section to remove concept primers (DCT/quantisation, what EXIF is) that duplicate references/rule.md and assume Claude's knowledge.

Add a verification/feedback step in the Fix section — e.g. re-run Lighthouse or check Transfer Size in DevTools and re-encode if savings remain — so the batch operation has an explicit validate-then-retry loop.

Move or fold the duplicated "Why it matters" sizing example (8MB DSLR vs 200KB) into the reference rather than restating it in the overview body.

DimensionReasoningScore

Conciseness

The body is mostly efficient, but the intro and "Explain" section restate JPEG/PNG/DCT/EXIF mechanics Claude already knows (e.g. "JPEG compression works by converting pixel data to frequency components (DCT) and quantising..."), which is unnecessary padding also duplicated in references/rule.md.

2 / 3

Actionability

It gives concrete, copy-paste-ready values for every format — mozjpeg quality 80 progressive=true, pngquant quality 65-80, oxipng, SVGO, WebP quality 80, AVIF quality 60 effort 6 — matching the fully-executable-guidance anchor.

3 / 3

Workflow Clarity

The Check and Fix sections are numbered sequences, but auditing/re-encoding every image is a batch operation with no explicit validation or verify-and-retry checkpoint in the body itself (verification lives only in the reference), which caps workflow clarity at 2.

2 / 3

Progressive Disclosure

The body is a clear overview with well-organized sections and a single well-signaled, one-level-deep pointer to references/rule.md, which exists as a real file holding the detailed implementation guidance.

3 / 3

Total

10

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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, complete, and well-triggered, covering both the concrete review actions and an explicit Use-when clause tied to natural image/performance terminology. It has a clear niche with low conflict risk.

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" — matching the anchor for multiple specific concrete actions.

3 / 3

Completeness

It explicitly answers both what (review/check those dimensions) and when via a clear "Use when reviewing image assets, markup, and CDN or build transforms" trigger, satisfying both halves.

3 / 3

Trigger Term Quality

It covers natural terms a user would say for this task (image assets, markup, loading strategy, above-the-fold) alongside the domain vocabulary (CDN, build transforms), giving good natural-keyword coverage.

3 / 3

Distinctiveness Conflict Risk

It is scoped narrowly to image-optimization review with distinct triggers, making it unlikely to fire for unrelated 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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