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c4-container

Expert C4 Container-level documentation specialist.

29

Quality

22%

Does it follow best practices?

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

The canonical home for this skill is c4-container 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 placeholder brackets rather than actionable guidance for Claude. It lacks a clear workflow for how to actually create C4 container documentation, provides no validation steps, and is verbose with generic content that Claude already understands. The Mermaid diagram example and OpenAPI template provide some concrete value, but the overall skill reads more like a blank form than an expert instruction set.

Suggestions

Replace the generic four-bullet instruction list with a concrete, sequenced workflow: e.g., 1) Identify deployment units from code/config, 2) Map components to containers, 3) Document interfaces, 4) Generate diagram, 5) Validate completeness against checklist.

Add explicit validation checkpoints, such as verifying all inter-container communication protocols are documented, all components are assigned to exactly one container, and all external dependencies are captured.

Replace placeholder templates with one fully worked, realistic example showing a complete container documentation for a concrete system (e.g., an e-commerce platform), then keep the template as a secondary reference.

Remove explanatory content Claude already knows (C4 model basics, what containers are, key principles from c4model.com) and focus on project-specific conventions and decision criteria.

DimensionReasoningScore

Conciseness

The content is heavily padded with template placeholders (e.g., '[Container Name]', '[Description]') that provide no actionable value. It explains C4 concepts Claude already knows, includes verbose sections like 'Key Distinctions' and 'Example Interactions' that add little, and the OpenAPI template is generic boilerplate. Most of the content is structural scaffolding rather than meaningful instruction.

1 / 3

Actionability

The Mermaid diagram example and OpenAPI spec template are somewhat concrete and could be adapted, but the core instructions are vague ('Clarify goals, constraints, and required inputs', 'Apply relevant best practices'). The templates use placeholder brackets throughout rather than providing a realistic worked example that demonstrates the actual synthesis process.

2 / 3

Workflow Clarity

There is no clear multi-step workflow for creating container documentation. The instructions section has four bullet points that are generic platitudes rather than a sequenced process. There are no validation checkpoints, no feedback loops, and no guidance on how to verify the output is correct or complete. For a task involving synthesizing deployment architecture, this is a significant gap.

1 / 3

Progressive Disclosure

There is a reference to 'resources/implementation-playbook.md' for detailed examples, and references to component-level docs (c4-component-name.md), but no bundle files exist to support these references. The content itself is somewhat structured with headers, but includes too much inline template content (OpenAPI spec, full Mermaid example) that could be in separate reference files.

2 / 3

Total

6

/

12

Passed

Description

22%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.

This description is far too terse and vague to be effective for skill selection. It relies on buzzwords ('Expert', 'specialist') without describing any concrete actions, and completely lacks a 'Use when...' clause. The only redeeming quality is the mention of 'C4 Container-level' which provides some domain specificity.

Suggestions

Replace vague 'specialist' label with concrete actions, e.g., 'Generates C4 Container diagrams, documents system containers and their interactions, creates PlantUML or Structurizr DSL representations of container-level architecture.'

Add an explicit 'Use when...' clause, e.g., 'Use when the user asks about C4 modeling, container diagrams, architecture documentation, or system decomposition at the container level.'

Include natural trigger terms users might say, such as 'architecture diagram', 'container view', 'C4 model', 'system architecture', 'PlantUML', 'Structurizr'.

DimensionReasoningScore

Specificity

The description uses vague language with no concrete actions listed. 'Expert' and 'specialist' are buzzwords that don't describe what the skill actually does (e.g., generate diagrams, write documentation, create container views).

1 / 3

Completeness

The 'what' is extremely vague ('documentation specialist' says almost nothing about concrete capabilities), and there is no 'when' clause or explicit trigger guidance whatsoever.

1 / 3

Trigger Term Quality

'C4' and 'Container-level' are relevant domain keywords that a user familiar with C4 modeling might use, but common variations like 'architecture diagram', 'system context', 'PlantUML', or 'structurizr' are missing.

2 / 3

Distinctiveness Conflict Risk

'C4 Container-level' provides some niche specificity that distinguishes it from generic documentation skills, but 'documentation specialist' is broad enough to overlap with other documentation-related skills.

2 / 3

Total

6

/

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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