How to Use AI to Write Technical Documentation in 2026 (ADRs, Runbooks, RFCs)

## Quick Answer

AI writes strong first drafts of ADRs, RFCs, runbooks, and architecture docs when you provide structure (via templates), context (code + diagrams), and audience. Always human-edit for accuracy.

- Templates beat free-form prompts every time - AI is better at rewriting than drafting from scratch — sketch bullets first - Runbooks must be tested by someone unfamiliar with the system

## What You'll Need

- A docs home: Fumadocs, Docusaurus, MkDocs, Notion - Templates for each doc type - AI IDE with access to your codebase - Review process (PR-based for docs)

## Steps

1. **Standardize templates.** ADRs (Michael Nygard format), RFCs (Rust-lang style), runbooks (SRE Google style). 2. **Provide context.** Paste relevant code, architecture diagrams (Mermaid), and existing docs. 3. **Sketch bullets.** Write 10 bullets covering what you want — AI expands them better than free-form. 4. **Generate the draft.** Prompt: `Using this ADR template, write an ADR for choosing pgvector over Qdrant.` 5. **Add diagrams.** Ask for Mermaid: `Create a sequence diagram for this login flow.` 6. **Human edit for accuracy.** Especially numbers, dates, and decisions. 7. **Review with an outsider.** Fresh eyes catch unclear passages. 8. **Version with code.** Docs-as-code: MDX in Git, reviewed via PR.

## Common Mistakes

- **Vague prompts.** `Write docs for my API` produces generic fluff. - **Skipping decision rationale.** ADRs must explain why alternatives were rejected. - **Untested runbooks.** Runbooks that haven't been exercised are fiction. - **AI-invented metrics.** Always replace fabricated numbers with real ones.

## Top Tools

| Tool | Use | |------|-----| | Fumadocs | MDX-based docs site | | Docusaurus | Versioned docs | | Mermaid | Diagrams as code | | Claude Code | Repo-aware drafting | | Vale | Prose linting |

## FAQs

**What goes in an ADR?** Context, decision, consequences, alternatives considered.

**How long should an RFC be?** 1-5 pages. Longer loses readers.

**Can AI write runbooks?** Yes — but test each step on a non-prod system before publishing.

**Should docs live with code?** Yes — `/docs` folder in the repo, deployed via CI.

**Does AI know my team's conventions?** Only if you include a style guide in the prompt.

**Can AI update stale docs?** Yes — diff the code, ask: `Update these docs to match the new code.`

## Conclusion

AI lowers the activation energy for technical writing. Use templates, sketch bullets, let AI expand, human edit. [Misar Blog](https://misar.blog) publishes free templates for ADRs, RFCs, and runbooks.