scheduler-yield

Use when reviewing JavaScript that performs synchronous loops over large datasets, recursive tree traversals, or bulk DOM updates that may exceed 50 ms on mid-range devices.

Quality

62%

Does it follow best practices?

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Securityby

Passed

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tessl review fix ./skills/scheduler-yield/SKILL.md

Quality

Content

57%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.

The body is a clean, well-structured overview that correctly pushes implementation detail into a single real reference file — an exemplary progressive-disclosure layout. Its weaknesses are all in substance: the intro duplicates the Quick Reference and restates known concepts, the Fix/Check sections give directives without any in-body executable example, and the workflow has no verification step for confirming the refactor actually unblocked the main thread.

Suggestions

Drop the redundant opening paragraph or the first Quick Reference bullet — they state the same 50 ms/INP fact twice, and that fact is background knowledge Claude already has.

Add a minimal in-body snippet (e.g. the yieldToMain() helper's 5-line core) or a one-line API signature so the Fix section is executable without opening the reference.

Add a verification step to the workflow, such as 'Confirm the refactored loop yields: chunk durations under 50 ms measured via performance.now(), and the page stays interactive during processing.'

Dimension	Reasoning	Score
Conciseness	The opening paragraph ('Any JavaScript task longer than 50 ms blocks the browser's main thread, preventing it from processing clicks, keyboard events, and rendering frames') duplicates the first Quick Reference bullet ('Tasks longer than 50 ms block input and hurt Interaction to Next Paint (INP)') and restates long-task/INP facts Claude already knows. Mostly efficient but could be tightened to the Quick Reference alone, matching anchor 3.	3 / 5
Actionability	Concrete guidance is present — the Fix section names the API ('scheduler.yield() with a MessageChannel fallback'), the threshold, and the target patterns — but the body contains no executable code, deferring implementation entirely to references/rule.md. This matches anchor 3 (some concrete guidance, incomplete in the body) rather than 4, since the Fix section is directive prose rather than executable steps.	3 / 5
Workflow Clarity	A clear section sequence exists (Check, Fix, Explain, Code Review) but no validation checkpoints appear anywhere — no measuring task duration, no verifying input responsiveness after the refactor. Steps listed with checkpoints missing matches anchor 3; not a destructive or batch operation, so no cap applies, but there is no verification step to justify 4.	3 / 5
Progressive Disclosure	The ~35-line body is a well-organized overview (Quick Reference, Check, Fix, Explain, Code Review) 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 151-line reference containing executable code. The overview/implementation split is appropriate and navigation is trivial, matching anchor 5.	5 / 5
	Total	14 / 20 Passed

Description

67%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.

The description has a strong, explicit trigger clause with concrete code-pattern conditions and a measurable threshold, but it is entirely when-focused: it never states what the skill does (applying scheduler.yield() with a fallback), and it lacks the natural user vocabulary (long tasks, main thread blocking, jank, INP) that would help it fire on real requests.

Suggestions

State the 'what' explicitly, e.g. prepend a capability statement like 'Refactor blocking JavaScript to yield via scheduler.yield() with a MessageChannel fallback' before the 'Use when' clause.

Add natural trigger terms users actually say — 'long tasks', 'main thread blocked', 'page freezes/jank', 'INP', 'responsive' — so the skill fires on conversational phrasing, not just code-pattern inspection.

Mention 'scheduler.yield' or 'yield to the main thread' in the description to disambiguate from adjacent performance skills like Web Workers or DOM batching.

Dimension	Reasoning	Score
Specificity	Names the domain ('reviewing JavaScript') and several concrete trigger conditions ('synchronous loops over large datasets, recursive tree traversals, or bulk DOM updates that may exceed 50 ms'), but the actual action the skill applies (scheduler.yield) is not mentioned, leaving a minor gap in coverage.	4 / 5
Completeness	An explicit 'Use when...' clause with concrete conditions is present, but the 'what' is only weakly stated as 'reviewing JavaScript' — the skill's actual fix (yield via scheduler.yield with a MessageChannel fallback) is unstated. Both what and when exist with one side weak, matching anchor 4 rather than the fully explicit anchor 5.	4 / 5
Trigger Term Quality	Relevant technical keywords are present ('JavaScript', 'synchronous loops', 'tree traversals', 'DOM updates'), but the natural terms users would actually say — 'long tasks', 'main thread blocking', 'freeze', 'jank', 'INP', 'performance' — are all missing. This is more than 'a few' missing synonyms, so it fits anchor 3 rather than 4.	3 / 5
Distinctiveness Conflict Risk	A clear niche (long-task yielding) with a specific 50 ms threshold and mid-range device qualifier, but related JavaScript performance skills (Web Workers, DOM batching, virtualization) could also trigger on 'loops' and 'DOM updates' since no scheduler/long-task term disambiguates. Mostly distinct with minor overlap risk, matching anchor 4.	4 / 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/scheduler-yield/SKILL.md
Commit: 7bfd868

Reviewed: 1 day ago

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