What do I need to connect a number through WhatsApp Coexistence?

In short: the WhatsApp Business app on the number, version 2.24.17 or newer and in regular use, a Facebook account with two-factor authentication, and a computer to run the connection with your phone at hand. No CNPJ or company registration is needed to connect.

The checklist

• The number runs on the WhatsApp Business app (not regular WhatsApp), on Android or iPhone, version 2.24.17 or newer. This is the only requirement Meta publishes.
• The number is in regular use. Meta may refuse numbers with little recent activity and does not publish the threshold; in practice about 7 days of real use has been enough.
• A personal Facebook account with two-factor authentication on. It is only used to authorize the connection.
• The number is not connected to another provider.
• A computer to run the connection, with your phone at hand to confirm it in the WhatsApp Business app.

Inside Meta's window

• Choose Connect a WhatsApp Business app, never Create a WhatsApp Business account. If Meta asks you to delete your account, stop.
• A security check about a new device or location keeps the Next button spinning until you clear it at business.facebook.com, in the same browser.
• Meta checks eligibility here, before anything is authorized. If it refuses the number, ZapClaw receives no access; see number not eligible.
• The app asks whether to share your chat history. It is optional; the contact list is always synced.

After connecting

• Linked devices are disconnected and can be linked again, except WhatsApp for Windows and WearOS, which Meta does not support with Coexistence.
• Keep opening the app on your main phone: Meta disconnects the number after about 14 days without it.
• Meta turns off disappearing messages, view-once and live location in one-to-one chats, broadcast lists become read-only, and group chats are not synchronized to the API.
• A Coexistence number sends up to 20 messages per second, a limit Meta fixes.