javascript-expert

Expert JavaScript developer specializing in modern ES6+ features, async patterns, Node.js, and browser APIs. Use when building JavaScript applications, optimizing performance, handling async operations, or implementing secure JavaScript code.

Quality

68%

Does it follow best practices?

Impact

—

No eval scenarios have been run

Securityby

Passed

No known issues

Fix and improve this skill with Tessl

tessl review fix ./skills/javascript-expert/SKILL.md

Quality

Content

55%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This skill provides excellent actionable code examples and clear TDD workflow, but is severely bloated with unnecessary explanations of concepts Claude already knows. The content would benefit greatly from being split into multiple files (patterns, security, testing) with SKILL.md serving as a concise overview with navigation links.

Suggestions

Remove sections 1-3 entirely (Overview, Core Principles, Core Responsibilities) - these explain concepts Claude already knows and add no actionable value

Extract implementation patterns (section 5-6) into a separate PATTERNS.md file and reference it from the main skill

Extract security standards (section 7) into a separate SECURITY.md file

Reduce the main SKILL.md to a quick-start TDD workflow example and navigation links to detailed reference files

Dimension	Reasoning	Score
Conciseness	Extremely verbose at ~800+ lines. Explains concepts Claude already knows (what ES6 features are, what promises are, basic programming concepts). Contains extensive lists of expertise areas and principles that don't add actionable value.	1 / 3
Actionability	Provides fully executable, copy-paste ready code examples throughout. Every pattern includes working JavaScript code with clear before/after comparisons (dangerous vs safe). Test examples are complete and runnable.	3 / 3
Workflow Clarity	TDD workflow is clearly sequenced with explicit steps (write failing test → implement minimum → refactor → verify). Includes validation commands and checklists for each phase. The multi-phase checklist provides clear verification checkpoints.	3 / 3
Progressive Disclosure	Monolithic wall of text with no references to external files. All content is inline despite being far too long for a single skill file. No navigation structure or links to separate reference materials for patterns, security, or testing.	1 / 3
	Total	8 / 12 Passed

Description

82%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

This description has good completeness with an explicit 'Use when' clause and decent trigger term coverage for JavaScript developers. However, it uses role-based framing ('Expert JavaScript developer specializing in') rather than action-based language, and lacks specific concrete actions like 'debug promises', 'refactor callbacks', or 'implement API calls'. The description would benefit from more action verbs and slightly more distinctive triggers.

Suggestions

Replace role-based framing with concrete actions: instead of 'Expert JavaScript developer specializing in', use 'Writes, debugs, and refactors JavaScript code using modern ES6+ features'

Add more specific action verbs to improve specificity: 'handles promises, implements async/await patterns, builds Node.js servers, interacts with DOM and browser APIs'

Dimension	Reasoning	Score
Specificity	Names the domain (JavaScript) and mentions areas like 'ES6+ features, async patterns, Node.js, browser APIs' but uses role-based framing ('Expert JavaScript developer specializing in') rather than listing concrete actions. No specific verbs describing what it actually does.	2 / 3
Completeness	Explicitly answers both what (JavaScript development with ES6+, async patterns, Node.js, browser APIs) and when ('Use when building JavaScript applications, optimizing performance, handling async operations, or implementing secure JavaScript code').	3 / 3
Trigger Term Quality	Good coverage of natural terms users would say: 'JavaScript', 'ES6+', 'async', 'Node.js', 'browser APIs', 'performance', 'async operations'. These are terms developers naturally use when seeking JavaScript help.	3 / 3
Distinctiveness Conflict Risk	While JavaScript-specific, terms like 'building applications', 'optimizing performance', and 'secure code' could overlap with general coding skills or other language-specific skills. The JavaScript focus helps but isn't maximally distinctive.	2 / 3
	Total	10 / 12 Passed

Validation

75%

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 — 12 / 16 Passed

Validation for skill structure

Criteria	Description	Result
skill_md_line_count	SKILL.md is long (1137 lines); consider splitting into references/ and linking	Warning
metadata_version	'metadata' field is not a dictionary	Warning
license_field	'license' field is missing	Warning
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	12 / 16 Passed

Repository: martinholovsky/claude-skills-generator
Commit: 1086ef2

Reviewed: 5 months ago

Table of Contents

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