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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.

Quality

66%

Does it follow best practices?

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tessl review fix ./skills/c4-context/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

55%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 usable documentation template and an executable Mermaid C4Context example, organized into clearly labeled sections. Its main weaknesses are the absence of any sequenced workflow with validation checkpoints for producing the documentation, and several padded/duplicated sections that inflate token cost without adding guidance.

Suggestions

Add an explicit numbered workflow (e.g., 1. Identify the system boundary and purpose, 2. Enumerate personas and features, 3. Map user journeys, 4. Catalog external systems, 5. Render the Mermaid diagram, 6. Verify every persona, feature, and external system appears in the diagram) with a validation checkpoint before finishing.

Cut the generic "Instructions" section and merge the overlapping "Example Interactions" and "Output Examples" into the existing use-when and template sections to remove duplication.

Turn the bare "Related Documentation" placeholders into real links (or remove them if no container/component skill files exist) so navigation is not left dangling.

DimensionReasoningScore

Conciseness

The template and executable Mermaid example earn their tokens, but the generic "Instructions" section ("Apply relevant best practices and validate outcomes"), "Example Interactions", and "Output Examples" largely duplicate other sections and read as padding. Mostly efficient but could be tightened by roughly a third, fitting the middle anchor better than the 'noticeably verbose' anchor 2.

3 / 5

Actionability

The Mermaid C4Context block is real, executable syntax, and the fill-in template plus key principles give concrete, directly usable guidance; minor gaps remain (no guidance on eliciting personas or what makes a good journey step). Not a 5 because the generic instructions and placeholder text leave some execution details to inference.

4 / 5

Workflow Clarity

There is no sequenced process for producing the documentation — the template section order only implies a rough sequence, steps are poorly defined, and there are no validation checkpoints (e.g., verifying the diagram includes every identified persona and external system). This matches 'rough sequence present but many gaps; validation absent'; not a 3 because no steps are actually listed as workflow steps.

2 / 5

Progressive Disclosure

A single SKILL.md with clear, well-labeled sections and no nested or dangling file references; the core template appropriately lives inline for a documentation skill. Minor gaps: "Related Documentation" entries are bare placeholder text pointing to nothing, and the ~140-line body could arguably split the template into a reference file. Fits 'good structure; most content appropriately placed' better than anchor 3.

4 / 5

Total

13

/

20

Passed

Description

63%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 does a good job of stating what the skill does with specific, third-person action verbs covering the full C4 context documentation scope. Its main weakness is the complete absence of a 'when to use' trigger clause, which caps completeness and limits trigger term quality. Adding explicit trigger phrases would also help distinguish it from sibling C4-level skills.

Suggestions

Add a 'Use when...' clause with concrete trigger phrases, e.g., "Use when the user asks for a C4 context diagram, system context documentation, persona or user journey mapping, or a high-level system overview."

Include natural user variations and synonyms such as "system landscape", "architecture overview", or "C4 level 1" to improve trigger term coverage.

Briefly differentiate from sibling C4 skills (e.g., "Context level only — not container or component diagrams") to reduce overlap risk with closely related skills.

DimensionReasoningScore

Specificity

"Creates high-level system context diagrams, documents personas, user journeys, system features, and external dependencies" lists five concrete actions that comprehensively cover the C4 context-level scope, matching the top anchor rather than the 'minor gaps' of anchor 4.

5 / 5

Completeness

The 'what' is clearly and specifically stated, but there is no 'Use when...' clause or equivalent trigger guidance, which caps completeness at 3 per the judging guidelines; it is not a 2 because the 'what' is concrete and multi-part.

3 / 5

Trigger Term Quality

Domain keywords like "C4 Context-level", "system context diagrams", "personas", and "user journeys" are relevant, but the description contains no explicit trigger phrases or natural user variations (e.g., "Use when creating a C4 context diagram"), matching the 'some relevant keywords but missing common variations' anchor.

3 / 5

Distinctiveness Conflict Risk

"C4 Context-level documentation specialist" carves out a mostly distinct niche, but sibling C4 skills (container, component, code levels) would create minor overlap risk since no explicit triggers distinguish when this skill versus those should fire.

4 / 5

Total

15

/

20

Passed

Validation

93%

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

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

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

Warning

Total

15

/

16

Passed

Repository

sickn33/agentic-awesome-skills

Path

skills/c4-context/SKILL.md

Reviewed

Table of Contents

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