Attach Webhook
Authentication
Request
Name for a new webhook (required if no webhookId).
HTTPS endpoint URL for a new webhook (required if no webhookId).
Event type filter for the subscription. Set to null to receive all events.
USER.TYPING is only supported for RCS agent senders, not phone numbers.
Response
Successfully attached webhook to the specified senders.
Senders that could not be found are returned in the failed array with error details.
Senders that were successfully attached (phone numbers in E.164 format or RCS agent IDs).

