What you're building: an AI agent that answers your customers on WhatsApp 24/7 — understands the question, remembers the client, books appointments, updates your sheets, and replies in seconds. Stack: Claude (the brain) + n8n (the hands) + WhatsApp (the face). Self-hosted n8n makes it a $0-infrastructure build.

Thanks for commenting AGENT! This is the exact architecture from the reel.

The architecture (5 blocks)

WhatsApp Trigger → AI Agent (Claude + Memory + Tools) → Reply to WhatsApp

1. Trigger — a customer messages you; the webhook wakes the workflow
2. Brain — Claude reads it and decides what to do (the system prompt below is the personality)
3. Memory — conversation history per customer, so it remembers names, orders, context
4. Actions — tools the agent can use: calendar booking, Google Sheets, Slack notification, email
5. Reply — the answer lands back in WhatsApp in seconds

Step 1 — n8n

• Fastest: n8n Cloud (paid from €24/mo) · $0 route: self-hosted Community Edition — unlimited workflows, free forever (any ~$5 VPS or even a home machine; guide to n8n free options is in my Free AI Guides hub)

Step 2 — Connect WhatsApp

• In n8n add the WhatsApp Business Cloud trigger node
• It needs a (free) Meta developer app: developers.facebook.com → create app → add WhatsApp product → copy the token & phone number ID into n8n credentials
• Test number works instantly; production number needs a business verification
• 💸 Cost note: replies inside the 24-hour customer-service window are free; only business-initiated template messages are billed by Meta

Step 3 — The Brain (AI Agent node)

• Add n8n's AI Agent node right after the trigger