Nobody likes writing documentation.

It's tedious. It gets outdated. It feels like work that doesn't ship features.

But good docs matter—for users, for your future self, for anyone who might help maintain the code someday.

AI is genuinely good at this. Documentation is one of the tasks where AI assistance provides the most value with the least downside.

Why AI Excels at Docs

Documentation is a perfect AI task:

Structure is predictable. READMEs follow patterns. API docs have conventions. AI knows these formats.

The information exists. You're not creating—you're explaining. AI can read your code and describe it.

First drafts are the hard part. Getting started is friction. AI removes that friction. Editing is easier than writing.

Accuracy is verifiable. Unlike creative writing, you can check if docs are correct.

The README Generator

Start with the most common need:

Generate a README for this project. Include:
- Project description (based on what the code does)
- Installation instructions
- Basic usage example
- Configuration options
- License

[paste package.json or main files]

You'll get a solid first draft in seconds. Edit for accuracy and voice.

API Documentation

For functions, classes, and endpoints:

Document this function. Include:
- Description of what it does
- Parameter types and descriptions
- Return value
- Example usage
- Edge cases or errors

[paste function]

AI generates comprehensive docs from code. You verify and refine.

For full API documentation:

Generate API documentation for these endpoints.
Use markdown format with:
- Endpoint URL and method
- Request parameters
- Request body (with example)
- Response format (with example)
- Error responses

[paste route handlers or OpenAPI spec]

Inline Comments (Done Right)

I'm skeptical of AI-generated inline comments. But for complex code, AI can help:

Add comments to this code explaining the WHY, not the what.
Focus on:
- Non-obvious decisions
- Business logic reasons
- Gotchas future developers should know

Don't comment on obvious operations.

[paste code]

The key is asking for "why" comments. AI defaults to "what" comments, which are useless.

Changelogs and Release Notes

Summarize what changed:

Generate a changelog entry from these commits/changes:

Changes:
- [list of changes]

Format as:
- User-facing changes first
- Bug fixes
- Internal improvements
- Breaking changes (if any)

Write for end users, not developers.

[paste diff or commit list]

AI transforms technical changes into user-friendly release notes.

The Update Workflow

Documentation rots. AI can help maintain it:

Regular refresh: Periodically ask AI to compare docs against current code. "Does this README still accurately describe this codebase?"

Change-triggered updates: When you change code, ask AI to update related docs. "I changed this function—update its documentation."

Consistency checks: "Review these docs for inconsistencies, outdated references, or broken examples."

Build doc updates into your development process, not as an afterthought.

Onboarding Documentation

For new users or contributors:

Write a getting-started guide for a developer joining this project.
Include:
- Prerequisites
- Setup steps
- Project structure overview
- Where to start for common tasks
- Key concepts they need to understand

Base it on:
[paste relevant files: package.json, folder structure, main entry points]

The onboarding doc you'll wish you had written.

Voice and Tone

AI-generated docs can be bland. Fix this:

Specify voice: "Write in a friendly, practical tone. Assume the reader is a competent developer who just needs the facts."

Edit for personality: First drafts are for content. Editing passes add your voice.

Maintain consistency: Use the same prompt patterns to get consistent output across all docs.

The Doc Quality Check

Before publishing AI-generated docs:

  1. Verify accuracy. Does the code actually work as described?
  2. Test examples. Do the code snippets run?
  3. Check links. Do referenced files exist?
  4. Read as a newcomer. Does it make sense without context?
  5. Add what's missing. AI doesn't know your deployment quirks.

AI drafts. You validate. This order matters.

What Not to Document

More docs isn't always better:

Skip the obvious. Don't document getUser() returning a user.

Avoid duplication. Don't repeat what types already express.

Focus on the confusing. Document what needs explanation, not everything.

AI will generate docs for anything. Use judgment about what actually helps.

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