Messaging Window

WhatsApp only delivers free-form messages (text, images, documents) within 24 hours of the customer’s last inbound message. Outside that window only an approved template lands. This endpoint answers both halves of that problem in one call:

Can I send free-form right now? → window_open
Have they replied yet? → latest_inbound

curl "https://api.whatbot.in/public/v1/messaging-window?phone=919876543210" \
  -H "X-API-Key: wa_live_xxx"

Query parameters

Field	Type	Required	Description
phone	string	yes	The customer’s number, in any format. Normalised to E.164. A number that can’t be normalised returns 422.
since	string		An ISO timestamp. Only report `latest_inbound` if it is newer than this. A value that is not ISO 8601 returns 422 rather than being ignored; an empty value is treated as absent.

Response

Field	Type	Description
phone	string	The number, normalised to E.164.
conversation_id	string	The conversation, or `null` if they have never messaged you.
window_open	boolean \| null	`true` if a free-form message will be delivered right now, `false` if only a template will. `null` means we could not tell — see below.
window_known	boolean	`false` when the lookup failed and `window_open` is `null`.
last_inbound_at	string	When they last messaged you, or `null`.
seconds_remaining	number \| null	Seconds of free-form window left. `0` when closed, `null` when the window could not be determined.
latest_inbound	object	Their most recent message — `{id, type, text, timestamp}` — or `null`. `text` is `null` for a message with no text (e.g. a photo without a caption).

{
  "phone": "+919876543210",
  "conversation_id": "a5230fa7-...",
  "window_open": true,
  "window_known": true,
  "last_inbound_at": "2026-08-27T10:00:00Z",
  "seconds_remaining": 82800,
  "latest_inbound": {
    "id": "b1f0...",
    "type": "text",
    "text": "hi",
    "timestamp": "2026-08-27T10:00:00Z"
  }
}

When we cannot tell

If the lookup itself fails, this endpoint says so rather than guessing:

{
  "phone": "+919876543210",
  "conversation_id": null,
  "last_inbound_at": null,
  "window_open": null,
  "window_known": false,
  "seconds_remaining": null,
  "latest_inbound": null
}

Treat window_open: null as unknown, not open. It is deliberately not reported as false either — a contact who messaged you a minute ago has not suddenly gone quiet. Retry, or send with fallback_template_name so the send itself decides.

Polling for a reply

Timestamps in the response end in Z, so you can paste one straight back into a query string. Pass since to poll without re-reading the same message. Take the timestamp you last saw, and latest_inbound stays null until something genuinely newer arrives:

curl "https://api.whatbot.in/public/v1/messaging-window?phone=919876543210&since=2026-08-27T10:00:00Z" \
  -H "X-API-Key: wa_live_xxx"

This is what lets an automated caller ask someone to message in, watch for it, and switch to free-form the moment it lands — that inbound message is what opens the window.