critical-images

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

Quality

75%

Does it follow best practices?

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tessl review fix ./skills/critical-images/SKILL.md

Quality

Content

78%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 clean, well-structured overview that practices good progressive disclosure with a single verified reference file. It falls slightly short of top marks on conciseness (a redundant known-fact bullet), actionability (a generic Check step with no inline markup), and workflow clarity (implicit identification/validation details).

Suggestions

Drop the redundant Quick Reference bullet about LCP impact or fold it into the intro to remove a known-fact restatement.

Make the 'Check' section concrete — e.g. name how to identify critical images (hero/banner, above-the-fold in initial viewport) instead of 'Identify which images are critical for initial render'.

Include one short inline fetchpriority/preload markup snippet so the Fix step is copy-paste ready without opening the reference.

Dimension	Reasoning	Score
Conciseness	The body is lean and points to references instead of padding, but the opening LCP/20-40% background sentence and the Quick Reference bullet 'Critical images directly impact LCP Core Web Vital' restate facts Claude already knows and duplicate each other.	4 / 5
Actionability	Concrete attribute-level guidance like 'Use fetchpriority=\'high\' on LCP images' and 'Remove loading=\'lazy\' from above-the-fold images' is present, but the 'Check' section ('Identify which images are critical for initial render') is generic and no inline markup example appears in the body itself.	4 / 5
Workflow Clarity	The Check → Fix → Explain → Code Review sections give a clear sequence and even mention confirming the fix in DevTools, but the identification step and validation specifics are only implicit in the body (they live in the reference file), leaving minor checkpoint gaps.	4 / 5
Progressive Disclosure	The body is a short, well-organized overview with a single clearly signaled one-level-deep reference ('For full implementation details, code examples, and framework-specific guidance, see references/rule.md') that verifiably exists and contains exactly that content.	5 / 5
	Total	17 / 20 Passed

Description

71%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 description with an explicit 'Use when' clause and concrete review dimensions, hindered by a when-clause that mirrors the what and by missing the most natural performance vocabulary (LCP, preload, hero image, lazy loading). Distinctiveness is moderate given overlap with other image rules.

Suggestions

Rewrite the when-clause with distinct user-sayable triggers, e.g. 'Use when the user mentions LCP, hero images, preloading, lazy loading, or above-the-fold performance.'

Add the missing natural trigger terms (LCP, Core Web Vitals, preload, hero image, lazy loading) to broaden keyword coverage.

Sharpen distinctiveness by emphasizing loading priority/fetch strategy over generic size checking, which overlaps sibling image-format rules.

Dimension	Reasoning	Score
Specificity	The description names 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' — which is specific, but the review/check framing leaves minor gaps versus fully comprehensive coverage.	4 / 5
Completeness	Both what and when are explicitly present ('Use when reviewing image assets, markup, and CDN or build transforms...'), but the when-clause largely restates the what rather than adding distinct trigger phrases, so it is not a clear 5.	4 / 5
Trigger Term Quality	Good keyword coverage including natural terms like 'image assets', 'markup', 'CDN', and 'above-the-fold impact', but common user phrasings such as 'LCP', 'hero image', 'preload', and 'lazy loading' are missing.	4 / 5
Distinctiveness Conflict Risk	The loading-priority focus is somewhat distinct, but 'Check encoded size, rendered size' overlaps with sibling image-optimization rules (formats, sizing, compression) in the same checklist, so it could still trigger for closely related skills.	3 / 5
	Total	15 / 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/critical-images/SKILL.md
Commit: 7bfd868

Reviewed: 1 day ago

Table of Contents

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