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skill-developer

Comprehensive guide for creating and managing skills in Claude Code with auto-activation system, following Anthropic's official best practices including the 500-line rule and progressive disclosure pattern.

47

Quality

49%

Does it follow best practices?

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SecuritybySnyk

Passed

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tessl review fix ./skills/skill-developer/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

63%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 skill demonstrates excellent progressive disclosure and good actionability with concrete templates and test commands, but suffers from significant verbosity — many sections explain concepts Claude already knows (skill types, enforcement levels, skip conditions) at unnecessary length. The duplicated Quick Reference Summary at the end, while potentially useful, adds to the bloat. Trimming explanatory prose and removing redundancy could cut this by 40% without losing any actionable content.

Suggestions

Remove or drastically condense the 'Skill Types' and 'Enforcement Levels' sections — these can be reduced to a simple table (type | enforcement | when to use) rather than multi-paragraph explanations with characteristics lists.

Eliminate the 'Quick Reference Summary' section at the end, which largely duplicates the main content above it, or alternatively restructure the skill to use only the summary format and remove the verbose sections above.

Cut explanatory phrases like 'Purpose: What this skill helps with', 'Characteristics:', and 'When to Use:' headers within subsections — Claude understands these concepts and the information can be conveyed more efficiently with inline annotations.

DimensionReasoningScore

Conciseness

Significantly verbose with extensive explanation of concepts Claude already understands (what guardrails are, what domain skills are, what enforcement levels mean). The 'Skill Types' section, 'Enforcement Levels' section, and 'Skip Conditions' section all over-explain concepts that could be conveyed in a fraction of the space. The 'Quick Reference Summary' at the end largely duplicates content already covered above.

2 / 5

Actionability

Provides concrete executable test commands, a usable JSON template for skill-rules.json, and a clear SKILL.md template with frontmatter. However, some guidance remains high-level (e.g., 'Refine patterns based on testing' without showing what refinement looks like), and the hook code examples are test invocations rather than showing how to write the hooks themselves.

4 / 5

Workflow Clarity

The 5-step Quick Start workflow is clearly sequenced with concrete commands at each step. The testing checklist is thorough. However, there's no explicit validation/feedback loop — Step 4 says 'Refine Patterns' but doesn't specify what to check for or how to verify success vs failure. Since this isn't a destructive/batch operation, the missing feedback loop doesn't cap the score at 3.

4 / 5

Progressive Disclosure

Excellent progressive disclosure structure with a clear overview in the main file and well-signaled, one-level-deep references to six separate files (TRIGGER_TYPES.md, SKILL_RULES_REFERENCE.md, HOOK_MECHANISMS.md, TROUBLESHOOTING.md, PATTERNS_LIBRARY.md, ADVANCED.md), each with a brief description of what it contains. Navigation is easy and intuitive.

5 / 5

Total

15

/

20

Passed

Description

36%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 identifies its domain (skill creation in Claude Code) and references some specific concepts (500-line rule, progressive disclosure), but it reads more like a document title than a functional skill description. It lacks concrete action verbs describing what the skill actually does and entirely omits a 'Use when...' clause, making it difficult for Claude to know when to select this skill over others.

Suggestions

Add an explicit 'Use when...' clause with trigger phrases like 'Use when the user asks to create a skill, write a skill.md file, set up auto-activation, or needs guidance on skill structure and best practices.'

Replace the vague 'comprehensive guide for creating and managing' with specific actions like 'Generates skill.md files with proper YAML frontmatter, structures skill content following the 500-line rule, configures auto-activation triggers.'

Include natural user terms and synonyms such as 'skill file', 'skill.md', 'custom skill', 'skill template', and 'skill format' to improve trigger term coverage.

DimensionReasoningScore

Specificity

Names the domain ('creating and managing skills in Claude Code') but the actions are generic ('creating and managing'). Mentions specific concepts like '500-line rule' and 'progressive disclosure pattern' but these describe guidelines rather than concrete actions the skill performs.

2 / 5

Completeness

The 'what' is vaguely stated as a 'comprehensive guide for creating and managing skills' but lacks specificity about concrete actions. There is no explicit 'when' clause — no 'Use when...' or equivalent trigger guidance, which should cap this at 3, but the weak 'what' brings it down to 2.

2 / 5

Trigger Term Quality

Includes some relevant keywords like 'skills', 'Claude Code', 'auto-activation', '500-line rule', and 'progressive disclosure'. However, it misses natural user phrases like 'write a skill', 'skill.md', 'YAML frontmatter', 'skill file', or 'how to create a skill'.

3 / 5

Distinctiveness Conflict Risk

The mention of 'skills in Claude Code' and 'auto-activation system' provides some specificity, but 'comprehensive guide' and 'best practices' are generic enough to overlap with other documentation or meta-skills about Claude Code configuration.

3 / 5

Total

10

/

20

Passed

Validation

90%

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

Validation10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

10

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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