Writing Documentation

Writing Documentation

Goal

Ensure the system is understandable, usable, and maintainable by humans (developers and users) through high-quality, up-to-date documentation.

When to Use

• Adding a new feature (update User Guide / README).
• Changing an API (update OpenAPI/Swagger).
• Onboarding new team members (update Setup Guide).
• Before "finishing" a task.

Instructions

1. The README.md

The front page of the project.

• Hook: What does this do? (1 sentence).
• Start: How to run it? (3 commands max).
• Stack: What tech is used?

2. API Documentation

Auto-generate where possible, but curate the descriptions.

• OpenAPI: Use comments/decorators to generate Swagger specs.
• Examples: Provide real JSON request/response examples.
• Errors: Document all possible error codes, not just 200 OK.

3. Architecture Decision Records (ADRs)

Document why a decision was made.

• "We chose PostgreSQL over MongoDB because..."
• Keep them immutable.

4. Code Comments

• Why, not What: Don't explain syntax (i++ // increment i). Explain intent (// retry 3 times to handle network blips).
• Public Interface: Document public functions/classes with docstrings.

Constraints

✅ Do

• DO: Keep docs close to code (README in repo, Swagger in code).
• DO: Update docs in the same PR as the code change.
• DO: Use "Mermaid.js" for diagrams in Markdown.

❌ Don't

• DON'T: Let docs drift from code (incorrect docs are worse than no docs).
• DON'T: Use jargon without definition.
• DON'T: Write wall-of-text paragraphs; use lists and headers.

Output Format

• README.md
• docs/*.md
• Code comments / Docstrings.

Dependencies

• shared/git-workflow/SKILL.md