service-worker

Use when auditing repeat-visit performance, adding offline support, or evaluating PWA readiness for a web application.

Quality

67%

Does it follow best practices?

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Securityby

Passed

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tessl review fix ./skills/service-worker/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.

A well-structured, appropriately progressive-disclosed overview that keeps the SKILL.md lean by offloading detail to references/rule.md. Its weaknesses are limited actionability (no executable code) and a workflow with no validation checkpoints, plus a mildly padded intro.

Suggestions

Add a minimal executable registration snippet (e.g. a navigator.serviceWorker.register call) so guidance is copy-paste ready rather than descriptive.

Trim the intro's benefit/marketing framing and replace it with a one-line purpose statement that assumes Claude's knowledge.

Insert a verification checkpoint after registration (e.g. confirm the SW is active/controller) to give the workflow an explicit validation step.

Dimension	Reasoning	Score
Conciseness	The body is mostly tight and sectioned, but the intro spends tokens on benefits Claude largely already knows ('programmable network proxy', 'cut load times by 50–90%', 'critical for users on mobile or low-bandwidth connections'), which is mild padding. Not a 3 because of that explanatory/marketing framing; not a 1 because it is not verbose to the point of explaining basic concepts at length.	2 / 3
Actionability	The Quick Reference lists concrete steps ('Register a service worker', 'Use an install event to pre-cache critical assets') but provides no executable code, and Check/Fix/Explain/Code Review describe rather than instruct. Not a 3 because nothing is copy-paste ready; not a 1 because the steps name specific, real actions rather than staying vague.	2 / 3
Workflow Clarity	Quick Reference gives a recognizable sequence (register → install → choose cache strategy → activate), but there are no validation checkpoints or verification steps for confirming the worker registered or caches are valid. Not a 3 because validation is absent; not a 1 because the sequence is clearly listed.	2 / 3
Progressive Disclosure	The body is a well-organized overview (Quick Reference, Check, Fix, Explain, Code Review) that defers full detail to a clearly signaled, one-level-deep reference ('see references/rule.md', verified to exist). Not a 2 because navigation is clean and content is appropriately split rather than inlined.	3 / 3
	Total	9 / 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.

A strong, concise description with an explicit trigger clause and concrete actions, clearly anchored to the PWA/service-worker domain. Its main weakness is trigger-term coverage and a mild overlap risk with broader performance-auditing skills.

Suggestions

Add the most common user keywords — 'service worker', 'caching', 'progressive web app', 'offline mode' — to broaden trigger-term coverage.

Sharpen the 'what' by leading with the core capability (e.g. 'Registers and configures a service worker for caching and offline support') before the 'Use when' clause, to distinguish it from general performance skills.

Dimension	Reasoning	Score
Specificity	Names the PWA/service-worker domain and three concrete actions — 'auditing repeat-visit performance', 'adding offline support', 'evaluating PWA readiness' — matching the anchor that lists multiple specific concrete actions. Not a 2 because it goes beyond naming a domain and some actions to enumerating several distinct capabilities.	3 / 3
Completeness	Explicit 'Use when' clause answers the when, and the action verbs ('auditing', 'adding', 'evaluating') convey what the skill does. Not a 2 because the when is explicit rather than implied, and the what is stated through concrete actions.	3 / 3
Trigger Term Quality	Includes natural user phrases like 'offline support', 'PWA readiness', and 'repeat-visit performance', but omits common variations users would say such as 'service worker', 'caching', 'progressive web app', or 'offline mode'. Not a 3 because coverage of natural terms is incomplete; not a 1 because several genuinely user-facing keywords are present.	2 / 3
Distinctiveness Conflict Risk	The PWA/service-worker niche is fairly distinct, but 'auditing repeat-visit performance' could overlap with general performance-auditing skills. Not a 3 because of that overlap risk; not a 1 because it is clearly more specific than generic 'helps with performance'.	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/service-worker/SKILL.md
Commit: 48405aa

Reviewed: about 7 hours ago

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