A WhatsApp AI agent with n8n and Claude, no code

What you need (and what costs money)

• A Meta for Developers account (free). The WhatsApp test number is free.
• n8n: n8n Cloud has a free trial, then it's paid. The self-hosted Community edition is free if you run it yourself.
• An Anthropic API key for Claude. You pay per use (small amounts for a few messages), with a card on the Anthropic Console.

A real business number needs Meta business verification, and Meta charges for some message types. Check Meta's current WhatsApp pricing before you go live.

Get a free test number (Meta for Developers)

• Go to developers.facebook.com/apps → Create app (business use case).
• In your app, add the product WhatsApp → Set up.
• Open WhatsApp → API Setup: you get a test number, its Phone number ID and a temporary access token. Keep this tab open.
• Add your own phone number as a recipient, so the test number is allowed to message you.

n8n: add a WhatsApp Trigger

• Create a new workflow in n8n. Add the node WhatsApp Trigger, event messages (“On message received”).
• Create the credential it asks for with your Meta app details. n8n shows the exact fields and a link to its docs.

Add an AI Agent with Claude, and paste your business info

• Add the node AI Agent after the trigger. As its chat model, add Anthropic Chat Model and paste your Anthropic API key.
• As the user message, use the text of the incoming WhatsApp message.
• In System Message, paste your prices, hours and FAQs. Template:

You are the WhatsApp assistant for [BUSINESS NAME].
Prices: [service: price], [service: price].
Opening hours: [days, hours].
Bookings: [how / when].
FAQs:
- [question] → [answer]
- [question] → [answer]
Rules: be short and friendly. Only use the info above.
If you don't know, say a person will reply soon.

Send the reply with a WhatsApp node

• Add the node WhatsApp Business Cloud → Send message after the AI Agent.
• Phone number ID: the one from step 1. Recipient: the sender of the incoming message. Text: the output of the AI Agent.

Recipient: {{ $('WhatsApp Trigger').item.json.messages[0].from }}
Text: {{ $json.output }}

Field names can differ slightly between n8n versions: pick the sender and the agent output from the data panel if the expressions above don't match.

Turn it on and text it

• Switch the workflow to Active.
• From your phone, text the test number: “How much is [your service]?” The answer should arrive in a few seconds.
• Test 5 real questions from your customers before going live, and fix the System Message when an answer is wrong.