BusinessAccount object or directly via the client.
Check the 24h conversation window
Before sending a free-form message (text, image, video, etc.), check whether the conversation window is open. The window opens when the contact sends you an inbound message and expires 24 hours later.Send a text message
Send a template message
Send media messages
Within the 24-hour conversation window, you can send images, videos, audio, and documents by URL:Media URLs must be publicly accessible. Meta downloads the file once and delivers it natively in the recipient’s WhatsApp chat. Supported formats: JPEG/PNG (image), MP4 (video), OGG/MP3 (audio), PDF/DOCX (document).
Send interactive buttons
Send a message with up to 3 reply buttons. The recipient taps a button and you receive the response via webhook.message.received with:
message_type:"interactive"message_metadata.interactive_type:"button_reply"message_metadata.id: the button ID (e.g."confirm")message_metadata.title: the button label (e.g."Yes, confirm")

