WhatsApp setup checklist

1. Meta Developer Account

1. Create an account at developers.facebook.com.
2. Create a Meta Business Manager at business.facebook.com.
3. Complete business verification for production messaging (often 1–3 business days).

2. Meta App

1. Create a Business-type app; add the WhatsApp product.
2. Add Facebook Login for Business (embedded signup).
3. Copy App ID → META_APP_ID, App Secret → META_APP_SECRET.
4. Under Facebook Login for Business → Settings, add https://<your-app>/onboarding/whatsapp/callback and https://<your-app>/onboarding to Valid OAuth Redirect URIs.
5. In the same panel, set Allowed Domains for the JavaScript SDK to the bare domain (e.g. www.bm-relay.com) with no https:// and no trailing slash. A malformed entry surfaces in the browser as “Feature unavailable” after the user signs in.
6. Under App Settings → Basic → App Domains, add the bare domain too (e.g. bm-relay.com). After changing this, re-complete the Data Use Checkup or Meta will keep Login paused.

3. Webhook

1. Callback URL: https://<your-api>/api/v1/webhooks/whatsapp
2. Set the same verify token in Meta and in META_WEBHOOK_VERIFY_TOKEN.
3. Subscribe to messages, message_template_status_update, account_update, phone_number_name_update, business_capability_update; verify and save.

4. Before going live

• Production number registered and verified; display name approved.
• At least one message template approved for campaigns.
• Webhook receives a test event from Meta.
• Onboarding reaches live_ready for your tenant.