w3c-compliant

Use when reviewing templates, rendered HTML, or shared components related to Validate HTML against W3C standards. Validate the final browser-facing markup, not just the source framework abstraction.

Quality

66%

Does it follow best practices?

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Securityby

Low

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tessl review fix ./skills/w3c-compliant/SKILL.md

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 skill is well-structured for progressive disclosure with a clean pointer to a real reference file, but the body is held back by redundancy between Check/Fix, concept explanation Claude already knows, and a lack of executable commands or an explicit validate-fix-revalidate loop.

Suggestions

Drop the opening motivation line and the 'Explain' section's restatement of why validation matters; Claude already knows invalid HTML harms compatibility and accessibility.

Merge the Check and Fix sections into one explicit sequence with a feedback loop, e.g. '1. Validate at validator.w3.org 2. Fix errors 3. Re-validate until clean 4. Then address warnings'.

Add at least one executable command, such as an `html-validate` invocation or a CI snippet, to lift actionability from describing to instructing.

Dimension	Reasoning	Score
Conciseness	The Quick Reference bullets are reasonably tight, but the opening motivation line and the "Explain" section restate why invalid HTML is bad (a concept Claude already knows), and the Check and Fix sections overlap heavily, so it could be tightened below level 3 without reaching fully verbose level 1.	2 / 3
Actionability	Concrete pointers appear (validator.w3.org, html-validate, common issue types) but there is no executable command or code example — the Check/Fix sections describe rather than instruct with copy-paste-ready steps, matching level 2.	2 / 3
Workflow Clarity	A loose order exists (validate, fix errors then warnings, integrate into CI/CD) but the validate -> fix -> re-validate feedback loop is only implicit and the Check/Fix split muddies the sequence, so checkpoints are missing rather than explicit as required for level 3.	2 / 3
Progressive Disclosure	The body is a concise overview with sections and a clearly signaled one-level-deep pointer to references/rule.md (a real file) for implementation details, matching the level 3 anchor for simple skills under 50 lines.	3 / 3
	Total	9 / 12 Passed

Description

75%

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 has an explicit trigger clause and a clear, distinct niche, but the capability statement is a single repeated action awkwardly fused with the trigger phrasing. Trigger-term coverage is reasonable but missing common natural variations.

Suggestions

Rewrite the trigger so the skill name is not embedded mid-sentence, e.g. 'Use when reviewing templates, rendered HTML, or shared components to confirm the rendered markup is W3C-valid.'

Broaden trigger terms to include phrasings users actually say, such as 'check HTML validity', 'HTML validation errors', or 'validate my markup'.

Name additional concrete actions if the skill performs them (e.g. 'report unclosed tags, invalid nesting, and missing attributes') to lift specificity to level 3.

Dimension	Reasoning	Score
Specificity	Names the domain (W3C HTML validation) and a concrete action ("Validate the final browser-facing markup"), but it is essentially a single repeated action rather than a list of multiple distinct concrete capabilities, so it falls short of level 3.	2 / 3
Completeness	It explicitly answers what ("Validate HTML against W3C standards", "Validate the final browser-facing markup") and when via an explicit "Use when..." clause, satisfying both halves required for level 3.	3 / 3
Trigger Term Quality	Relevant natural terms appear ("templates, rendered HTML, or shared components", "W3C"), but common variations a user might say (e.g. "check my HTML is valid", "HTML errors") are missing and the phrasing is awkward, matching level 2 rather than full coverage at level 3.	2 / 3
Distinctiveness Conflict Risk	The W3C validation niche is specific and the disambiguator "not just the source framework abstraction" narrows the trigger, making it unlikely to fire for the wrong skill.	3 / 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/w3c-compliant/SKILL.md
Commit: 48405aa

Reviewed: about 6 hours ago

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