render-blocking

Use when auditing slow page loads, heavy assets, or rendering delays related to Eliminate render-blocking resources. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.

Quality

73%

Does it follow best practices?

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Securityby

Passed

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tessl review fix ./skills/render-blocking/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 body is well-structured and properly delegates detail to a single clearly-signaled reference, achieving good progressive disclosure. It is weakest on actionability and workflow clarity because the body itself carries no executable code and only implicit verification checkpoints.

Suggestions

Drop or trim the opening sentence explaining what render-blocking is; Claude already knows this, and the Quick Reference conveys the same idea more efficiently.

Add one small inline code snippet (e.g. a defer/async script tag or a media-query lazy-load pattern) so the body is actionable without forcing a jump to the reference.

Make the verify step explicit in the workflow — e.g. 'After changes, re-run Lighthouse/DevTools and confirm FCP improves before considering the fix complete' — to add a real feedback loop.

Dimension	Reasoning	Score
Conciseness	The body is lean with terse bullet-based Quick Reference and short Check/Fix/Explain sections, but the opening 'Render-blocking resources prevent the browser from painting anything...' explains a concept Claude already knows, and 'Fix' restates defer/async already covered in Quick Reference.	2 / 3
Actionability	Concrete techniques are named (defer, async, media queries, inline critical CSS, avoid @import), but the body provides no executable code and defers all examples to references/rule.md, leaving the SKILL.md guidance incomplete for direct execution.	2 / 3
Workflow Clarity	Check/Fix/Explain/Code Review give a loose audit-to-fix sequence and the Code Review section asks to 'describe the measurement method used to confirm the issue', but validation checkpoints are implicit rather than explicit and there is no fix→re-measure feedback loop.	2 / 3
Progressive Disclosure	SKILL.md acts as a concise overview with a clearly signaled, one-level-deep pointer ('For full implementation details, code examples, and framework-specific guidance, see references/rule.md') to a real, well-organized reference file.	3 / 3
	Total	9 / 12 Passed

Description

90%

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 strong: it pairs an explicit 'Use when' trigger with natural performance vocabulary and a clear, tool-backed niche. It is slightly less comprehensive in enumerating distinct capabilities, framing most action around one audit-and-recommend workflow.

Dimension	Reasoning	Score
Specificity	Names the domain and concrete actions ('auditing slow page loads, heavy assets, or rendering delays', 'Verify the actual bottleneck in DevTools, Lighthouse, or field data', 'recommending changes'), but the actions revolve around a single audit workflow rather than a comprehensive list of distinct capabilities.	2 / 3
Completeness	Clearly answers both what (audit/verify render-blocking bottlenecks and recommend fixes) and when, via an explicit 'Use when auditing slow page loads, heavy assets, or rendering delays...' trigger clause.	3 / 3
Trigger Term Quality	Includes natural terms a user would say — 'slow page loads', 'heavy assets', 'rendering delays', 'DevTools', 'Lighthouse' — giving good coverage of the way performance issues are actually described.	3 / 3
Distinctiveness Conflict Risk	Tightly scoped to the render-blocking niche with named tooling (DevTools, Lighthouse, field data), making it unlikely to trigger for unrelated performance or general skills.	3 / 3
	Total	11 / 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/render-blocking/SKILL.md
Commit: 48405aa

Reviewed: about 8 hours ago

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