How to create an AI agent on WhatsApp

Creating a real WhatsApp AI agent means: (1) a WhatsApp Cloud API number, (2) a system prompt + knowledge, (3) human handoff, and (4) preferably coexistence so you do not kill the phone. An unofficial bot on WhatsApp Web is not enough. With 42agents you build it white-label: the agency owns brand and price; Pro from USD 39/account/mo; BYOK for the model; 7-day trial.

Steps

1. Step 1

   Define the use case

   Pick inbound sales, support, or booking. Write 5–10 real intents and what must escalate to a human. Without this the prompt stays generic.

2. Step 2

   Prepare the number and WABA

   The number must be eligible for Cloud API (Meta rules). Ideally the same number the business already uses, with coexistence to keep the app and WhatsApp Web.

3. Step 3

   Open the 42agents account

   Sign up at https://dashboard.42agents.app/sign-up. Choose Pro (USD 39/account/mo) or Premium (USD 117/mo from 3 accounts). Start the 7-day trial.

4. Step 4

   Connect Cloud API

   Complete embedded signup / onboarding as a Meta Tech Provider. Verify webhooks receive test messages.

5. Step 5

   Configure the agent

   Paste the system prompt (see sales/support templates), load FAQ or catalog into knowledge, set BYOK (OpenAI or OpenRouter), and handoff rules to the inbox (3 users included).

6. Step 6

   Test end to end

   Message from a real phone: greeting, objection, human request, after hours. Tune the prompt before sending ad traffic.

7. Step 7

   Ship the CTA

   Point wa.me / QR / click-to-WhatsApp at that number. Monitor quality rating and templates if you will exit the 24-hour window.

Important notes

• A “WhatsApp Web chatbot” with an eternal QR is not Cloud API and does not meet Meta policy at scale.
• Meta per-conversation fees are not included in the 42agents plan.
• Start with one use case; do not mix complex sales and legal support in the same prompt on day one.