Skill library / Claude Code

API Documentation skill for Claude Code

API docs drift the moment code changes. This skill has Claude Code read your handlers and types directly and regenerate accurate reference docs, with request and response examples that actually match.

What it's good for

• REST APIs in Express, FastAPI, Next.js or Rails
• Keeping a docs/ folder in sync before release
• Onboarding docs for internal APIs

How the skill works

1. Locate route definitions and their request/response types
2. For each endpoint record method, path, auth, params and status codes
3. Write a curl example and a sample JSON response
4. Note errors and edge cases from the handler code
5. Update docs/api.md, preserving any hand-written sections

Built-in rules

• Document only what the code does, not what it should do
• Never include real secrets or tokens in examples
• Mark deprecated endpoints clearly

Example

You: “Document the /orders endpoints”
Result: docs/api.md updated with 5 endpoints, params tables, curl examples and error codes.

SKILL.md template

Save as api-documentation/SKILL.md.

---
name: api-documentation
description: "Generates and updates API reference docs from route handlers and types, including endpoints, parameters, responses and examples. Use when the user asks to document an API, endpoint or update the API docs."
---

# API Documentation

## Workflow
1. Locate route definitions and their request/response types
2. For each endpoint record method, path, auth, params and status codes
3. Write a curl example and a sample JSON response
4. Note errors and edge cases from the handler code
5. Update docs/api.md, preserving any hand-written sections

## Rules
- Document only what the code does, not what it should do
- Never include real secrets or tokens in examples
- Mark deprecated endpoints clearly

How to install in Claude Code

Unzip into .claude/skills/ in your project (or ~/.claude/skills/ for all projects) and invoke it with /skill-name.

Pro tip

Add a scripts/ helper that lists routes so the skill doesn't need to search the whole repo each time.

FAQ

Related skills

• Code Review skill for Claude Code
• Commit Message skill for Claude Code
• Pull Request Description skill for Claude Code