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legacy-js

Use when auditing slow page loads, heavy assets, or rendering delays related to Avoid serving legacy JavaScript to modern browsers. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.

49

Quality

53%

Does it follow best practices?

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SecuritybySnyk

Passed

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tessl review fix ./skills/legacy-js/SKILL.md
SKILL.md
Quality
Evals
Security

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 content is well-structured with a clean progressive-disclosure split to a real reference file, but the body itself stays descriptive — it explains a known concept and names techniques without executable code or explicit validation checkpoints.

Suggestions

Drop or tighten the opening concept-explainer ('Modern browsers can execute ES6+ code faster...') — Claude already knows this; lead with the actionable technique instead.

Add at least one inline executable snippet in 'Fix' (e.g. the module/nomodule script tags or a Vite `build.target` setting) instead of deferring all code to the reference.

Add an explicit validation checkpoint to the workflow (e.g. 'After changing the build target, confirm via Lighthouse/DevTools that legacy-javascript chunks are no longer served before considering the fix done').

DimensionReasoningScore

Conciseness

The body is mostly lean, but it opens by explaining a concept Claude already knows ('Modern browsers can execute ES6+ code faster and more efficiently...') and the 'Explain' section is meta-instructional rather than substantive.

2 / 3

Actionability

It names concrete techniques ('differential serving (module/nomodule)', 'set a modern target') but the body contains no executable code or commands — all specifics are deferred to references/rule.md.

2 / 3

Workflow Clarity

The Check → Fix → Explain → Code Review sequence is present, but there are no explicit validation checkpoints in the body; the Code Review step only implicitly references 'the measurement method used to confirm the issue'.

2 / 3

Progressive Disclosure

A concise overview body points via a clearly signaled, one-level-deep reference ('see references/rule.md') to the full implementation details, and that referenced file exists and is well-organized.

3 / 3

Total

9

/

12

Passed

Description

50%

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 some concrete tools, but is structurally awkward — the rule title is inserted into the prose and the skill's actual capability is never stated, leaving both the 'what' and the trigger terms underdeveloped.

Suggestions

Rewrite as a clean third-person capability statement followed by a trigger clause, e.g. 'Configures builds to stop serving transpiled ES5 and polyfills to modern browsers. Use when auditing bundle size, slow page loads, or rendering delays caused by legacy JavaScript.'

Add natural technical trigger terms users would actually say: 'transpile', 'polyfill', 'bundle size', 'module/nomodule'.

Remove the embedded rule title ('related to Avoid serving legacy JavaScript to modern browsers') so the description reads as a capability, not a heading.

DimensionReasoningScore

Specificity

It names concrete actions ('auditing slow page loads', 'Verify the actual bottleneck in DevTools, Lighthouse, or field data') but never states the skill's core capability (configuring builds to avoid legacy JS), and the rule title is awkwardly embedded mid-sentence.

2 / 3

Completeness

An explicit 'Use when...' trigger is present, but the 'what' is weak — it describes a verification process ('Verify the actual bottleneck... before recommending changes') rather than what the skill actually does.

2 / 3

Trigger Term Quality

Natural terms like 'slow page loads', 'heavy assets', 'rendering delays', and 'legacy JavaScript' appear, but common technical variations users would say ('bundle size', 'transpile', 'polyfill') are missing.

2 / 3

Distinctiveness Conflict Risk

'slow page loads, heavy assets, or rendering delays' is broad performance language that could overlap with many performance skills, narrowed only by the 'legacy JavaScript' reference.

2 / 3

Total

8

/

12

Passed

Validation

93%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

Total

15

/

16

Passed

Repository
thedaviddias/Front-End-Checklist
Reviewed

Table of Contents

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