image-optimization

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

Quality

68%

Does it follow best practices?

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Securityby

Passed

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tessl review fix ./skills/image-optimization/SKILL.md

Quality

Content

61%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.

A well-structured, actionable overview that delegates implementation detail to one reference file. It is held back by some restated background knowledge and the absence of explicit validation checkpoints in a batch workflow.

Suggestions

Trim the intro paragraph and 'Explain' section to remove general web-performance background Claude already knows, keeping only skill-specific guidance.

Add an explicit validation/verification checkpoint to the Fix workflow (e.g., re-scan after fixes and confirm served formats/sizes in DevTools Network tab) to support the batch operation.

Move the detailed 'Explain' and 'Code Review' prose into references/rule.md so the body stays a lean overview pointing to one level of detail.

Dimension	Reasoning	Score
Conciseness	Mostly efficient, but the intro ('Images typically account for 50%+ of page weight. Unoptimized images cause slow load times...') and parts of the Explain section restate web-perf concepts Claude already knows.	3 / 5
Actionability	Check and Fix give concrete, specific guidance — srcset widths '400w, 800w, 1200w, 1600w', '< 200KB for photos', '80% quality for photos, 60% for AVIF' — with only minor gaps; inline code lives in the reference rather than the body.	4 / 5
Workflow Clarity	Check/Fix/Explain/Code Review provide a clear sequence with numbered steps, but this batch image-scanning workflow lacks explicit validation checkpoints (e.g., verify-in-DevTools feedback loop), capping it at 3 per the batch-operation rule.	3 / 5
Progressive Disclosure	Well-organized into Quick Reference/Check/Fix/Explain/Code Review with a single clearly-signaled one-level reference ('see references/rule.md'); minor gaps because the body still inlines substantial Explain/Code Review prose.	4 / 5
	Total	14 / 20 Passed

Description

75%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.

A solid, specific description with an explicit trigger clause and concrete check targets. It clearly communicates both what the skill does and when to invoke it.

Dimension	Reasoning	Score
Specificity	Names the domain and several 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' — but stops short of the comprehensive multi-action list of a 5.	4 / 5
Completeness	Explicit 'Use when reviewing image assets, markup, and CDN or build transforms' answers when, and 'Check encoded size, rendered size, loading strategy, and above-the-fold impact together' answers what; both present but the what/when blur slightly rather than being crisply separate.	4 / 5
Trigger Term Quality	Good natural coverage with 'image assets', 'markup', 'CDN', 'build transforms', 'loading strategy', and 'above-the-fold', though common synonyms like WebP/AVIF/srcset/lazy loading are absent.	4 / 5
Distinctiveness Conflict Risk	'Optimize all images for web' with CDN/build-transform and above-the-fold framing carves a clear niche with minimal conflict risk, though it could still brush against general web-performance skills.	4 / 5
	Total	16 / 20 Passed

Validation

93%

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 — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
metadata_version	'metadata.version' is missing	Warning

	Total	15 / 16 Passed

Repository: thedaviddias/Front-End-Checklist
Path: skills/image-optimization/SKILL.md
Commit: 30756a7

Reviewed: 20 days ago

Table of Contents

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