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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. Synthesizes container and component documentation with system documentation to create comprehensive context-level architecture. Use when creating the highest-level C4 system context documentation.

46

Quality

49%

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Passed

No known issues

Optimize this skill with Tessl

npx tessl skill review --optimize ./.agent/skills/c4-context/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

22%

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

This skill is essentially a skeleton or template with no substantive content. The instructions are generic boilerplate that could apply to any skill, providing zero domain-specific guidance on C4 context-level documentation. While it attempts progressive disclosure through sub-skill references, the main file offers no actionable information about how to create system context diagrams, document personas, or synthesize architecture documentation.

Suggestions

Replace the generic instructions with concrete, C4-specific guidance: define what a system context diagram must contain (system boundary, actors, external systems), provide a template or example output in Mermaid/PlantUML/Structurizr DSL.

Add a clear workflow with sequenced steps, e.g.: 1. Identify personas → 2. Map external systems → 3. Define system boundary → 4. Create context diagram → 5. Validate against container-level docs.

Fill in the empty 'System Overview' section with actual content describing the purpose and scope of context-level documentation.

Add brief descriptions next to each sub-skill link explaining what it covers and when to use it, rather than using placeholder names like 'Feature Name' and 'Persona Name'.

DimensionReasoningScore

Conciseness

The content is relatively short but includes generic boilerplate instructions ('Clarify goals, constraints, and required inputs', 'Apply relevant best practices') that add no value and waste tokens. The 'Use this skill when' / 'Do not use this skill when' sections are tautological.

2 / 3

Actionability

The instructions are entirely vague and abstract — 'Apply relevant best practices and validate outcomes' and 'Provide actionable steps and verification' are meta-instructions with no concrete guidance, no executable code, no specific commands, and no examples of what a system context document should look like or how to produce one.

1 / 3

Workflow Clarity

There is no clear workflow or sequenced steps for creating a C4 context-level document. The four bullet points under Instructions are generic platitudes with no ordering logic, no validation checkpoints, and no feedback loops.

1 / 3

Progressive Disclosure

The skill does reference seven sub-skill files and one resource file, providing a one-level-deep structure. However, the sub-skill names are placeholder-like ('Feature Name', 'Persona Name'), the references lack any description of what each contains, and without bundle files it's impossible to verify these paths exist. The 'System Overview' header is empty.

2 / 3

Total

6

/

12

Passed

Description

77%

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 is a solid description that clearly articulates specific capabilities and includes an explicit 'Use when' trigger clause. Its main weaknesses are moderate trigger term coverage (missing common user phrasings) and potential overlap with other C4-level documentation skills due to the mention of synthesizing container and component documentation.

Suggestions

Add more natural trigger term variations users might say, such as 'architecture overview', 'system boundary diagram', 'C4 model level 1', or 'top-level architecture'.

Sharpen the distinctiveness by clarifying how this skill differs from container-level or component-level C4 skills, e.g., 'Use when creating the highest-level C4 system context documentation (Level 1), not for container or component diagrams.'

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions: creates high-level system context diagrams, documents personas, user journeys, system features, external dependencies, and synthesizes container/component documentation with system documentation.

3 / 3

Completeness

Clearly answers both 'what' (creates context diagrams, documents personas, user journeys, system features, external dependencies, synthesizes documentation) and 'when' with an explicit trigger clause: 'Use when creating the highest-level C4 system context documentation.'

3 / 3

Trigger Term Quality

Includes relevant terms like 'C4', 'context-level', 'system context diagrams', 'personas', 'user journeys', but misses common user variations like 'architecture diagram', 'system overview', 'context diagram', or 'C4 model'. The terms are somewhat specialized and may not match how users naturally phrase requests.

2 / 3

Distinctiveness Conflict Risk

The C4 context-level focus provides some distinction, but could overlap with other C4-level skills (container, component) since it mentions synthesizing container and component documentation. The 'Use when' clause helps narrow scope to 'highest-level' but the boundary between C4 levels could still cause confusion.

2 / 3

Total

10

/

12

Passed

Validation

81%

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

Validation9 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

frontmatter_unknown_keys

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

Warning

Total

9

/

11

Passed

Repository
Dokhacgiakhoa/antigravity-ide
Reviewed

Table of Contents

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