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c4-context

Expert C4 Context-level documentation specialist. Creates high-level system context diagrams, documents personas, user journeys, system features, and external dependencies.

36

Quality

32%

Does it follow best practices?

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tessl review fix ./plugins/antigravity-awesome-skills/skills/c4-context/SKILL.md

The canonical home for this skill is c4-context in sickn33/agentic-awesome-skills

SKILL.md
Quality
Evals
Security

Quality

Content

22%Scale 1-3

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

This skill is primarily a documentation template with placeholders rather than actionable guidance for Claude. While the Mermaid C4 diagram example is useful and concrete, the bulk of the content is verbose template scaffolding that Claude could generate on its own. The skill lacks a clear workflow for how to actually create C4 context documentation and wastes tokens on generic instructions and concepts Claude already understands.

Suggestions

Replace the generic 'Instructions' section with a concrete step-by-step workflow: e.g., 1. Read codebase entry points, 2. Identify external integrations from config/imports, 3. Draft personas from auth/role systems, 4. Generate Mermaid diagram, 5. Validate completeness against checklist.

Remove the template placeholders (e.g., '[Persona Name]', '[Feature Name]') and instead provide one complete, filled-in example of context documentation for a real or realistic system.

Cut the 'Use this skill when/Do not use this skill when', 'Example Interactions', 'Key Distinctions', and 'Limitations' sections - these consume tokens without adding actionable value for Claude.

Add validation checkpoints: e.g., verify all external systems found in code are represented in the diagram, verify all user roles map to personas, verify diagram renders correctly.

DimensionReasoningScore

Conciseness

The skill is extremely verbose with extensive template scaffolding (placeholder brackets like '[One-sentence description]', '[Persona Name]') that Claude doesn't need. It explains basic C4 concepts Claude already knows, includes unnecessary sections like 'Use this skill when/Do not use this skill when', 'Example Interactions', and 'Key Distinctions' that add little actionable value. The 'Output Examples' section is just a bullet list of what to produce rather than actual examples.

1 / 3

Actionability

The Mermaid diagram template is concrete and executable, which is valuable. However, most of the content is template scaffolding with placeholders rather than actionable instructions. The 'Instructions' section is extremely vague ('Clarify goals, constraints, and required inputs', 'Apply relevant best practices'). There's no concrete workflow for how to actually gather information and produce the documentation.

2 / 3

Workflow Clarity

There is no clear sequenced workflow for creating C4 context documentation. The instructions are four generic bullet points with no specific ordering, validation checkpoints, or feedback loops. The skill doesn't explain how to go from inputs to outputs - it just shows the template structure of the output. For a multi-step documentation task, this lacks any meaningful process guidance.

1 / 3

Progressive Disclosure

The skill references `resources/implementation-playbook.md` for detailed examples, which is good progressive disclosure. However, no bundle files are provided, so we can't verify this reference exists. The content itself is somewhat structured with clear sections, but includes too much inline template content that could be in a separate template file. References to 'Container Documentation' and 'Component Documentation' are vague with no actual links.

2 / 3

Total

6

/

12

Passed

Description

42%Scale 1-3

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 does well at listing specific concrete deliverables (context diagrams, personas, user journeys, etc.) and references the C4 framework, which adds domain specificity. However, it critically lacks any 'Use when...' guidance, making it harder for Claude to know when to select this skill. The description also uses a noun-phrase style ('Expert... specialist') rather than action-oriented third person, and could benefit from more natural trigger terms users would actually say.

Suggestions

Add an explicit 'Use when...' clause, e.g., 'Use when the user asks for C4 context diagrams, system architecture overviews, or needs to document how users and external systems interact with the system.'

Include more natural trigger terms and variations users might say, such as 'architecture diagram', 'system overview', 'C4 model', 'system boundary', 'external integrations', or 'high-level architecture'.

Rephrase from 'Expert... specialist' noun-phrase style to action-oriented third person, e.g., 'Creates high-level C4 context diagrams, documents personas, user journeys...'

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions: creates context diagrams, documents personas, user journeys, system features, and external dependencies. These are clearly defined deliverables.

3 / 3

Completeness

Describes what it does (creates context diagrams, documents personas, etc.) but completely lacks a 'Use when...' clause or any explicit trigger guidance for when Claude should select this skill. Per rubric guidelines, missing 'Use when' caps completeness at 2, and the 'when' is entirely absent, warranting a 1.

1 / 3

Trigger Term Quality

Includes some relevant terms like 'C4', 'context diagrams', 'personas', 'user journeys', but misses common user phrasings like 'architecture diagram', 'system overview', 'C4 model', or 'stakeholder mapping'. Users may not naturally say 'Context-level documentation specialist'.

2 / 3

Distinctiveness Conflict Risk

The 'C4 Context-level' qualifier provides some specificity, but terms like 'personas', 'user journeys', and 'system features' could overlap with UX design skills, product management skills, or other architecture documentation skills. Without explicit scoping, there's moderate conflict risk.

2 / 3

Total

8

/

12

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.

Validation — 10 / 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
popey/claude-code-skills
Reviewed

Table of Contents

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