c4-code

Expert C4 Code-level documentation specialist. Analyzes code directories to create comprehensive C4 code-level documentation including function signatures, arguments, dependencies, and code structure.

Quality

37%

Does it follow best practices?

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

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

Quality

Content

7%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 essentially an unfilled template with placeholder values throughout, providing no concrete guidance on how to actually analyze code and produce C4 code-level documentation. The bulk of the content is generic Mermaid diagram examples and a paradigm comparison table that, while informative, don't constitute actionable instructions. The skill lacks any real workflow, specific tools or commands, and validation steps.

Suggestions

Replace placeholder brackets with concrete instructions: specify actual tools/commands for extracting function signatures, class hierarchies, and dependencies (e.g., using AST parsers, ctags, or language-specific tools).

Add a clear step-by-step workflow: e.g., 1) List files in directory, 2) Parse each file for exports/classes, 3) Extract signatures, 4) Map dependencies, 5) Generate Mermaid diagram, 6) Validate output against source.

Move the extensive Mermaid diagram examples and paradigm comparison table into a separate reference file (e.g., `resources/diagram-templates.md`) and keep only a brief summary with a link in the main skill.

Add at least one concrete, end-to-end example showing input (a small code directory) and expected output (the completed C4 code-level documentation).

Dimension	Reasoning	Score
Conciseness	The skill is almost entirely a template with placeholder brackets ([Directory Name], [What this function does], etc.) rather than actual content. It includes extensive Mermaid diagram examples for multiple paradigms, a comparison table, and verbose explanations of when to use each diagram type—all of which are generic reference material that inflates token count without providing specific, actionable guidance for a particular codebase.	1 / 3
Actionability	The content provides no concrete, executable code or commands. Everything is a placeholder template or generic Mermaid diagram example. There are no actual steps for how to analyze a code directory—no commands to run, no specific tools to use, no concrete workflow for extracting function signatures or dependencies from source code.	1 / 3
Workflow Clarity	There is no clear multi-step workflow for actually performing C4 code-level documentation. The 'Instructions' section has four vague bullet points ('Clarify goals', 'Apply relevant best practices') with no sequencing, validation checkpoints, or error recovery. The skill doesn't explain how to go from a code directory to finished documentation.	1 / 3
Progressive Disclosure	There is a reference to `resources/implementation-playbook.md` for detailed examples, which shows some attempt at progressive disclosure. However, no bundle files are provided to support this reference, and the main document itself is a monolithic wall of template content and diagram examples that could be split into separate reference files.	2 / 3
	Total	5 / 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 is strong in specificity and distinctiveness, clearly identifying the C4 code-level documentation niche with concrete deliverables. However, it lacks an explicit 'Use when...' clause, which is critical for Claude to know when to select this skill. The trigger terms could also be expanded to cover more natural user phrasings.

Suggestions

Add an explicit 'Use when...' clause, e.g., 'Use when the user asks for C4 diagrams, code-level architecture documentation, or wants to map out code structure and dependencies.'

Include additional natural trigger terms users might say, such as 'architecture diagram', 'code map', 'codebase structure', 'component dependencies', or 'software architecture documentation'.

Dimension	Reasoning	Score
Specificity	Lists multiple specific concrete actions: 'Analyzes code directories', 'create comprehensive C4 code-level documentation', 'function signatures, arguments, dependencies, and code structure'. These are concrete, specific capabilities.	3 / 3
Completeness	Clearly answers 'what does this do' (analyzes code directories to create C4 code-level documentation with specific outputs), but lacks an explicit 'Use when...' clause or equivalent trigger guidance, which caps this at 2 per the rubric.	2 / 3
Trigger Term Quality	Includes relevant terms like 'C4', 'code-level documentation', 'function signatures', 'dependencies', 'code structure', but misses common user variations like 'architecture diagram', 'component diagram', 'code map', or file extensions. Users might not always say 'C4' specifically.	2 / 3
Distinctiveness Conflict Risk	The 'C4 Code-level documentation' niche is very specific and distinct. It's unlikely to conflict with general code documentation or other architecture skills because it explicitly targets the C4 model's code-level view with specific deliverables like function signatures and dependencies.	3 / 3
	Total	10 / 12 Passed

Validation

90%

Warnings & errors only

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

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	10 / 11 Passed

Repository: popey/claude-code-skills
Path: skills/c4-code/SKILL.md
Commit: a5a6601

Reviewed: 20 hours ago

Table of Contents

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