service-worker

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

Quality

61%

Does it follow best practices?

Run evals on this skill

Adds up to 20 points to the overall score

View guide

Securityby

Passed

No findings from the security scan

Fix and improve this skill with Tessl

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

Quality

Content

65%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 well-structured, lean overview that practices clean progressive disclosure by pointing to references/rule.md for implementation detail. Its weaknesses are the lack of any executable code or validation checkpoints in the body itself and a slightly padded intro paragraph.

Suggestions

Add one minimal copy-paste registration snippet inline so the skill is actionable without opening the reference.

Trim the intro benefits paragraph to one line; Claude already knows why service workers matter.

Add an explicit verification checkpoint (e.g. "Confirm Status: activated and running in DevTools → Application") to the Check or Fix section.

Dimension	Reasoning	Score
Conciseness	The body is lean with tight bullets and short Check/Fix/Explain/Code Review sections; the only over-explanation is the intro benefits paragraph ("cut load times on repeat visits by 50-90%... critical for mobile or low-bandwidth"), which states facts Claude already knows. Not 5 because that intro paragraph could be trimmed; not 3 because the padding is minor rather than pervasive.	4 / 5
Actionability	Names concrete strategies (cache-first, network-first, stale-while-revalidate) and a specific code-review checklist (flag missing install/activate handlers, cache-versioning, fetch handlers, stale-content patterns), but provides no executable code or commands in the body — all implementation is deferred to references/rule.md. Not 4 because nothing in the body is copy-paste ready; not 2 because the audit guidance is concrete rather than purely abstract.	3 / 5
Workflow Clarity	The Quick Reference gives a rough 4-step sequence (register → install → choose strategy → activate) and the Check/Fix/Explain/Code Review sections imply a methodology, but there are no validation checkpoints or feedback loops in the body. Not 4 because checkpoints are missing rather than minor; not 2 because a recognizable sequence is present.	3 / 5
Progressive Disclosure	The body is a concise overview with well-organized sections and a clearly signaled one-level-deep pointer — "see references/rule.md" — and that reference file exists and holds the detailed implementation. Not 4 because navigation is explicit and the split is appropriate rather than only "mostly" clear.	5 / 5
	Total	15 / 20 Passed

Description

58%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, specific trigger clause targeting a distinct PWA/offline niche, but it never states what the skill actually does and omits the most natural keywords ("service worker", "caching"). Adding an explicit capability statement and the missing trigger terms would materially improve it.

Suggestions

Add an explicit "what" clause before the trigger, e.g. "Registers and configures a service worker for caching and offline support. Use when..." so both what and when are answered.

Include the natural terms users actually say — "service worker", "caching", "cache assets" — alongside "PWA" and "offline support".

Keep the existing concrete triggers; they are the strongest part of the description.

Dimension	Reasoning	Score
Specificity	Names the domain and lists several concrete trigger tasks — "auditing repeat-visit performance", "adding offline support", "evaluating PWA readiness" — with only minor coverage gaps (e.g. no mention of registering/configuring the service worker itself). Not 5 because it does not comprehensively enumerate the skill's actual capabilities; not 3 because more than 1-2 concrete actions are given.	4 / 5
Completeness	Provides a strong, explicit "Use when..." clause but no standalone "what does this skill do" statement — the capability is only implicitly conveyed through the trigger tasks. Not 4 because both a clear "what" and "when" are required; not 2 because the "when" guidance is specific and explicit rather than vague.	3 / 5
Trigger Term Quality	Includes natural terms like "offline support", "PWA readiness", and "repeat-visit performance", but omits the most common user phrases "service worker" and "caching"/"cache", leaving common synonyms missing. Not 4 because those core terms are absent; not 2 because there is more than generic keyword coverage.	3 / 5
Distinctiveness Conflict Risk	Targets a clear niche (PWA / offline / repeat-visit performance) with fairly distinct triggers and only minor overlap risk with general performance or caching skills. Not 5 because terms like "performance" and "caching" could overlap with adjacent skills; not 3 because the PWA/offline framing is genuinely specific.	4 / 5
	Total	14 / 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/service-worker/SKILL.md
Commit: 30756a7

Reviewed: 9 days ago

Table of Contents

Discovery Implementation Validation

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.