Arnold Documentation
Documentation-first development for AI coding agents. Slash commands that run inside Claude Code, Cursor, Windsurf, and 30+ agents.
What is Arnold?
Arnold is a toolkit that keeps your documentation and code in sync. You write requirements in plain English, build with any AI coding agent, and Arnold tells you where docs and code have drifted apart.
It runs as slash commands inside your existing coding agent - no standalone CLI, no API key, no database. Just markdown files and shell scripts.
🦕 Arnold says
Arnold uses a 🦕 Jurassic Park personality because documentation should be alive, not extinct.
The Core Loop
Everything in Arnold revolves around a simple loop:
- Write docs -
/arnold:initscaffolds structured docs organized by feature - Build code - Use any coding agent you like, or let
/arnold:buildguide construction - Check for drift -
/arnold:checkreads docs and code, reports mismatches - Fix mismatches -
/arnold:resolvewalks you through each drift item - Repeat - Documentation stays alive. Code stays aligned.
> /arnold:check
🦕 ARNOLD CHECK REPORT
━━━━━━━━━━━━━━━━━━━━━━
Scanned: 4 feature docs, 23 source files
🔴 DRIFT DETECTED
━━━━━━━━━━━━━━━━━
1. auth: Session timeout
📄 Docs say: "Sessions expire after 24 hours"
💻 Code has: SESSION_TTL = 72 * 60 * 60
→ Docs say 24hr, code says 72hr. Which is right?
🟢 ALIGNED
━━━━━━━━━━
✓ payments: Stripe is the payment processor
✓ booking: Users cannot book the same class twice
Run /arnold:resolve to fix drift items.
Quick Links
- Installation - Get Arnold running in 60 seconds
- Your First 5 Minutes - Init, build, check, resolve
- Command Reference - All commands
- Drift Detection - The signature feature, explained
- Fitness Studio Example - A complete worked example