Sends a bulk message to multiple recipients (up to 50).
This endpoint allows you to send the same message to multiple phone numbers. All existing logic (including spam checks, delivery behavior, and visibility in the Bulk Messages UI tab) will remain the same for API-triggered sends.
Important: Message sending is asynchronous. This endpoint creates the bulk message batch and returns immediately with success=True, indicating the batch was created successfully. Individual messages are sent in the background. To check the delivery status of individual recipients, use the GET /message/bulk/{id} endpoint to retrieve the batch with delivery status information (attempted_send, error_message, delivery_status fields per recipient).
Added on Dec 28, 2025 for API v2.
Rate limit: 1200 per minute.