Quick Answer

Use AI to generate JSDoc/TSDoc inline, OpenAPI specs from your routes, and READMEs from your package.json plus directory tree. Cursor and Claude Code are best for repo-scale docs; Copilot is best for inline comments.

TSDoc generation is near-perfect for typed code
Never publish AI-generated docs without reading them once
Auto-regenerate docs on CI to prevent drift

What You'll Need

TypeScript/JavaScript project (docs workflows adapt to Python, Go, Rust)
An AI IDE or CLI
typedoc or jsdoc for generated output
Optional: Fumadocs, Mintlify, or Docusaurus for publishing

Steps

Generate JSDoc for a function. In Copilot: type /** above a function and press Tab. In Cursor: Add TSDoc to all exports in this file.
Include examples. Prompt: Add an @example block showing typical usage.
Generate README from scratch. Attach package.json, top-level folders, and prompt: Write a README with install, usage, API, and contributing sections.
Generate OpenAPI from Express/Fastify routes. Prompt: Read these route handlers and produce an OpenAPI 3.1 spec.
Run doc CI. Add typedoc --out docs to your build step.
Publish with Fumadocs. Self-hosted, free, MDX-powered.
Keep docs fresh. Run scripts/update-docs.ts via Husky pre-push: if source changed without doc changes, fail.

Common Mistakes

Letting AI invent function behavior. Always verify @returns and @throws match the code.
Generic examples. AI loves foo/bar/baz. Ask for real examples from your domain.
Outdated code blocks. Snippets in docs rot fast — test them in CI.
No ownership. Someone on the team must own docs or they die.

Top Tools

Tool	Best For
Mintlify Writer	Inline JSDoc/TSDoc
GitHub Copilot	Comment autocompletion
Cursor	Repo-wide README generation
TypeDoc	Publishing TS API reference
Fumadocs	Self-hosted docs site

Conclusion

Docs are the cheapest quality multiplier in software. With AI, the excuse "I don't have time to document" is gone. Set up TypeDoc + Copilot today; publish with Fumadocs. Misar Blog has templates for API docs in five frameworks.