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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.

63

1.34x
Quality

45%

Does it follow best practices?

Impact

97%

1.34x

Average score across 3 eval scenarios

SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./skills/c4-context/SKILL.md

The canonical home for this skill is c4-context in sickn33/antigravity-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 placeholder brackets rather than actionable guidance for Claude. While the Mermaid C4Context diagram example is a genuine strength, the bulk of the content is verbose boilerplate, vague instructions, and empty templates that don't teach Claude how to actually perform the task. The skill would benefit greatly from a clear workflow, concrete decision-making guidance, and trimming of content Claude already knows about C4 modeling.

Suggestions

Replace the four generic instruction bullets with a concrete sequenced workflow (e.g., 1. Read existing docs → 2. Identify personas → 3. Map features → 4. Document external systems → 5. Generate diagram → 6. Validate completeness) with explicit validation checkpoints.

Remove the empty template placeholders (e.g., '[One-sentence description]') and instead provide a single concrete filled-in example showing what good output looks like for a real system.

Trim the 'Use this skill when' / 'Do not use this skill when' sections and the 'Key Distinctions' section significantly — these are generic and don't add actionable value.

Move the large template structure to a separate referenced file and keep SKILL.md focused on the workflow, key principles, and one concrete example.

DimensionReasoningScore

Conciseness

The content is verbose and padded with template placeholders (e.g., '[One-sentence description of what the system does]'), boilerplate sections ('Use this skill when' / 'Do not use this skill when' with generic guidance), and explanations of C4 concepts Claude already knows. The 'Output Examples' section is a bullet list of vague descriptions rather than actual examples. Much of this could be significantly tightened.

1 / 3

Actionability

The Mermaid diagram template is concrete and executable, which is valuable. However, most of the content consists of empty templates with placeholder brackets rather than actionable instructions. The 'Instructions' section is extremely vague ('Clarify goals, constraints, and required inputs' / 'Apply relevant best practices'). The skill describes what to produce but doesn't give concrete guidance on how to gather information or make decisions.

2 / 3

Workflow Clarity

There is no clear sequenced workflow for creating context documentation. The instructions are four generic bullet points with no ordering logic, no validation checkpoints, and no feedback loops. For a multi-step documentation task (gather info → identify personas → map journeys → create diagram → validate), the absence of a clear process is a significant gap.

1 / 3

Progressive Disclosure

There is a reference to 'resources/implementation-playbook.md' for detailed examples, and mentions of related Container/Component documentation. However, the main file itself is quite long with inline template content that could be split out, and the references are not clearly signaled with links. The structure has sections but the organization mixes templates, instructions, and reference material without clear separation.

2 / 3

Total

6

/

12

Passed

Description

67%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 and carving out a distinct niche within C4 modeling. However, it lacks an explicit 'Use when...' clause which caps completeness, and the trigger terms lean toward specialized terminology that users may not naturally use when requesting this type of work.

Suggestions

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

Include more natural trigger term variations such as 'architecture diagram', 'system overview', 'high-level architecture', 'C4 model', and 'system boundary' to improve discoverability.

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

Clearly answers 'what does this do' with specific actions, but lacks an explicit 'Use when...' clause or equivalent trigger guidance. The 'when' is only implied by the nature of the capabilities listed.

2 / 3

Trigger Term Quality

Includes some relevant terms like 'C4', 'context diagrams', 'personas', 'user journeys', but misses common variations users might say such as 'architecture diagram', 'system overview', 'stakeholder mapping', or 'C4 model'. The term 'C4 Context-level' is somewhat specialized jargon.

2 / 3

Distinctiveness Conflict Risk

The 'C4 Context-level' qualifier creates a clear niche distinct from general documentation or other architecture diagram skills. It specifically targets one level of the C4 model, reducing overlap with container, component, or code-level diagram skills.

3 / 3

Total

10

/

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.

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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