progressive-jpeg

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

Quality

60%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./skills/progressive-jpeg/SKILL.md

Quality

Content

42%

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

The skill is well-structured for progressive disclosure with a clean pointer to a real reference file, but the body itself is repetitive and lacks any concrete, executable guidance or validation steps.

Suggestions

Move at least one concrete conversion command (e.g., `convert input.jpg -interlace JPEG output.jpg`) or a DevTools verification step into the body so the skill is actionable without opening the reference.

Collapse the redundant intro, Quick Reference, and Explain sections that repeat the same "blurry preview" explanation.

Add an explicit verification checkpoint (e.g., confirm progressive encoding with `identify -verbose image.jpg | grep Interlace`) to the Check or Fix workflow.

Dimension	Reasoning	Score
Conciseness	The body is short but restates the same "progressive JPEGs show a blurry preview" idea in the intro, Quick Reference, and Explain sections, and explains a concept Claude already knows.	2 / 3
Actionability	The body contains no executable code or commands—"Check if JPEG images are saved in progressive format" and "Convert baseline JPEGs to progressive format" describe rather than instruct, with all concrete tooling deferred to references/rule.md.	1 / 3
Workflow Clarity	Check/Fix/Explain/Code Review sections loosely imply a sequence, but there is no explicit ordering or validation/verification checkpoint in the body (e.g., confirming the format with `identify -verbose`).	2 / 3
Progressive Disclosure	The body is a concise overview that clearly signals a single one-level-deep reference—"see `references/rule.md`"—which exists as a real file with the implementation details.	3 / 3
	Total	8 / 12 Passed

Description

77%

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 states what the skill does and when to use it with concrete checks, but its trigger terms miss common phrasings and the opening trigger is broad enough to collide with other image rules.

Suggestions

Add common natural trigger terms users would actually say, e.g. "JPEG", "JPG", "images", or "image performance/loading".

Lead with the progressive-JPEG-specific trigger rather than the generic "reviewing image assets, markup, and CDN or build transforms" to reduce overlap with sibling image skills.

Dimension	Reasoning	Score
Specificity	Names 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"—rather than vague abstractions.	3 / 3
Completeness	Explicitly answers both what ("Check encoded size, rendered size, loading strategy, and above-the-fold impact together") and when (the "Use when reviewing image assets, markup, and CDN or build transforms..." trigger clause).	3 / 3
Trigger Term Quality	Includes relevant terms (image assets, markup, CDN, progressive JPEG, above-the-fold) but omits common natural variations a user might say such as plain "JPEG", "JPG", "images", or "page speed/performance".	2 / 3
Distinctiveness Conflict Risk	The lead trigger "reviewing image assets, markup, and CDN or build transforms" is broad and would overlap sibling image-optimization skills; only the trailing "related to Use progressive JPEG encoding" narrows the niche.	2 / 3
	Total	10 / 12 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/progressive-jpeg/SKILL.md
Commit: 48405aa

Reviewed: about 8 hours ago

Table of Contents

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