---
name: api-documentation-writer
description: Generate comprehensive API documentation including endpoint descriptions, request/response examples, authentication guides, error codes, and SDKs. Creates OpenAPI/Swagger specs, REST API docs, and developer-friendly reference materials. Use when users need to document APIs, create technical references, or write developer documentation.
---

# API Documentation Writer

Generate comprehensive, developer-friendly API documentation.

## Contents
- `references/documentation-structure.md` — every section to cover (overview, auth, endpoints, errors, rate limits, SDKs, webhooks, GraphQL)
- `references/output-template.md` — canonical REST Markdown template with worked examples
- `references/best-practices.md` — best practices, developer-experience tips, and the output quality checklist

## Workflow

1. Gather API information. Determine the API type (REST, GraphQL, WebSocket, gRPC), authentication method (API key, OAuth, JWT), base URL and versioning strategy, available endpoints and their purposes, request/response formats, and any rate limiting or usage restrictions.

2. Build the documentation structure. Cover every section in `references/documentation-structure.md`, ordering the most common operations first.

3. Generate the output. Follow `references/output-template.md` for REST APIs; adapt to schema, query, mutation, and subscription examples for GraphQL. Replace all placeholders with realistic example data and show both request and response.

4. Document errors and rate limits. Include the standard error response format, common error codes, troubleshooting guidance, limits, headers to check, and how to handle `429` responses.

5. Provide code samples in multiple languages (curl, JavaScript, Python) and link SDKs, Postman collections, or OpenAPI specs where available.

6. Verify quality against the checklist in `references/best-practices.md` before delivering.

## Example Triggers
- "Write API documentation for my REST endpoints"
- "Create OpenAPI spec for my API"
- "Document this GraphQL schema"
- "Generate developer docs for my webhook API"
- "Write authentication guide for API"

---

## Agent contract

_Added by Tacit's Skill Builder so agents use this skill predictably. Everything above this section is the
author's original, unchanged. This section restates what the skill already implies; verify it before relying on it._

**Before you start, ask for** (in one message; state assumptions if the user wants you to proceed):
- The API source: code, OpenAPI spec, or a list of endpoints
- API type, authentication method, base URL and versioning
- The audience (internal team, partners, public developers)

**Output format:**

```
API docs (Markdown)
- Overview and quick start
- Authentication
- Endpoints: method, path, parameters, request and response examples
- Errors and rate limits
- Code samples (curl, JavaScript, Python)
- Changelog
```

**When to stop and hand off to a human:**
- Endpoint behaviour isn't clear from the code or spec: ask the API owner rather than documenting a guess
- Examples would include real keys, tokens or customer data: use placeholders

_Original: [Api Documentation Writer](https://github.com/OneWave-AI/claude-skills/blob/main/api-documentation-writer/SKILL.md) by OneWave AI, licensed MIT. Changes: added this "Agent contract" section._


---

<!-- Original licence -->

MIT License

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