Name: javascript-mastery
Rating: 44.8 (1 reviews)
Author: administrakt0r

javascript-mastery

33+ essential JavaScript concepts every developer should know, inspired by [33-js-concepts](https://github.com/leonardomso/33-js-concepts).

Quality

47%

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tessl review fix ./plugins/AI-Agents-Safe-Coding-Skills-claude/skills/javascript-mastery/SKILL.md

The canonical home for this skill is javascript-mastery in administrakt0r/AI-Agents-Safe-Coding-Skills

Quality

Content

50%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 provides a well-organized, executable reference of JavaScript concepts, but it spends most of its tokens re-explaining basic concepts Claude already knows and inlines everything in SKILL.md rather than splitting detail into reference files.

Suggestions

Trim or remove sections covering concepts Claude already knows (primitives, basic coercion, map/filter/reduce, destructuring) and keep only the genuinely non-obvious material, or move the full reference into a bundled file.

Split the per-concept detail into reference files under references/ (e.g. references/async.md, references/closures.md) and have SKILL.md serve as a concise overview with one-level-deep links, improving progressive disclosure.

For any task-oriented sections, add explicit validation or verification steps so workflows have checkpoints rather than only conceptual exposition.

Dimension	Reasoning	Score
Conciseness	The ~640-line body is a JavaScript concept cheat sheet covering primitives, coercion, closures, hoisting, the event loop, and map/filter/reduce — concepts Claude already knows — which the rubric explicitly penalizes; per-section terseness keeps it just above the 'heavily padded' anchor 1.	2 / 5
Actionability	Code examples are executable, complete, and copy-paste ready with expected outputs shown, clearly above the pseudocode anchor; it sits at 4 rather than 5 because the snippets are breadth reference material rather than end-to-end task solutions covering specific common cases.	4 / 5
Workflow Clarity	This is a reference skill with no multi-step procedural workflow or validation checkpoints (and no destructive/batch operations), so the structure-plus-'When to Use' list lands at the 'steps/checkpoints missing' anchor 3.	3 / 5
Progressive Disclosure	No bundle files exist and all content is inlined in SKILL.md with no overview-to-detail split or reference-file pointers; good section headers keep it above anchor 2, but inlining a 640-line reference fits the 'content that should be separate is inline' anchor 3.	3 / 5
	Total	12 / 20 Passed

Description

45%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 clearly identifies the domain but is missing concrete actions and any 'Use when...' trigger guidance, which the rubric caps at completeness 3. Trigger-term coverage is limited to the single keyword 'JavaScript' without synonyms or variations.

Suggestions

Add a 'Use when...' clause with concrete trigger phrases, e.g. 'Use when explaining JavaScript concepts, debugging tricky JS behavior, or reviewing code for JS best practices.'

List 2-3 concrete actions the skill performs (e.g. 'Explains, debugs, and reviews JavaScript code') instead of only naming the topic.

Broaden trigger terms with natural synonyms users say (JS, ES6+, async, closures, event loop) to improve trigger-term quality and distinctiveness.

Dimension	Reasoning	Score
Specificity	The description names the domain ("33+ essential JavaScript concepts") but lists no concrete actions, matching the 'names the domain but actions are minimal or generic' anchor rather than the 1-2 concrete actions required for a 3.	2 / 5
Completeness	It clearly states what the skill is (JavaScript concepts) but provides no 'when' / 'Use when...' trigger guidance, and the rubric caps completeness at 3 when explicit trigger guidance is missing.	3 / 5
Trigger Term Quality	"JavaScript" is a natural term users would say, but coverage is limited to that single core term with no common variations (JS, ES6, debugging) or synonyms, fitting the 'some relevant keywords but missing common variations' anchor.	3 / 5
Distinctiveness Conflict Risk	It is scoped to JavaScript (distinguishable from non-JS skills) but extremely broad within JS as a comprehensive concept reference, so it could still overlap with many JS-related skills.	3 / 5
	Total	11 / 20 Passed

Validation

87%

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 — 14 / 16 Passed

Validation for skill structure

Criteria	Description	Result
skill_md_line_count	SKILL.md is long (649 lines); consider splitting into references/ and linking	Warning
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	14 / 16 Passed

Repository: administrakt0r/AI-Agents-Safe-Coding-Skills
Path: plugins/AI-Agents-Safe-Coding-Skills-claude/skills/javascript-mastery/SKILL.md
Commit: 57c135b

Reviewed: 4 days ago

Table of Contents

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