Landbot POSTs this payload to every registered message hook URL when a message moves through the channel (Web/WhatsApp; APIchat customer messages do NOT fire — see the APIchat webhook reference).

Authenticity: if you set a token on the hook, it is echoed as Authorization: Token <token> (a static shared secret — compare the full value; there is no HMAC). User-Agent: landbot/webhooks. Ordering: bursts can arrive out of order (~10–50 ms); sort by timestamp. Dedupe: the sentry-trace header is unique per message and stable across retries. Retries: non-2xx is retried on linear backoff (deltas ~5/10/15/20/25 s, ≥6 attempts). Return any 2xx (body ignored) to acknowledge.