Sending messages

WhatsApp allows two kinds of outgoing message, and choosing the right one is most of the job.

Free-form vs template

	Free-form (text, buttons, media)	Template
When allowed	Within 24 hours of the person's last message to you	Any time
Needs Meta approval	No	Yes, once per template
Meta charge	Free	Per message, by category and country

Details: the 24-hour window, explained.

check_recipient: decide before you send

Your assistant calls check_recipient with the phone number first. It returns:

• replyWindowOpen — true, false, or null when we have no record of them messaging you.
• optedOut — they replied STOP.
• approvedTemplates — each with its body and number of variables.
• recommendation — one sentence: reply free-form, use an approved template, or (only if nothing fits) create one.

Safeguards

• Free-form sends are refused when the window is known to be closed — otherwise Meta would accept and silently drop them.
• When the window state is unknown, the send goes ahead with a warning in the result.
• Template sends to opted-out numbers are refused.
• Every send counts against your plan's monthly allowance; when it's used up or the trial has ended, sending pauses with a clear reason.

"Accepted" isn't "delivered"

From your own app, the same rules apply through the REST API: POST /v1/messages with a template or text, and an Idempotency-Key so retries never double-send.

A successful send means Meta accepted the message. Delivery and read receipts arrive afterwards through the webhook and show in the inbox and in bulk-send stats. Don't tell a customer "it arrived" based on the send result alone.

From the dashboard

Reply from the Inbox. The reply box switches between free text and templates depending on the window, and fills template variables for you.