Credits will run out within a week
Sent once when the balance, at the average paid usage of the last 14 days, will last 7 days or less. Subscription credits and an upcoming renewal are taken into account. Checked hourly, so it can arrive up to an hour after the threshold is crossed; for an exact balance use credits_remaining on any API response.
Answer with any 2xx within 10 seconds, then do the work. Anything else (including a redirect) is retried after 1 min, 5 min, 30 min, 2 h, 6 h, 12 h, 24 h; after 8 attempts the event is given up. Order is not guaranteed.
Headers
t=<unix seconds>,v1=<hex>. v1 is HMAC-SHA256 of "<t>.<raw body>" with the endpoint secret. During a secret rotation a second v1 is present for 24 hours; accept the request if any v1 matches. Reject a t more than 5 minutes from your clock.
Same as id in the body, and the same on every retry. Deduplicate on it.
1 on the first try, then 2, 3… up to 8.
Payload
Example payload
{
"id": "evt_16f7c01502fda5436e8b7c4e"
}Response
Received. Any 2xx status counts; the body is ignored.
Changes
Webhooks have no change history: a webhook is keyed by its event name rather than a path and method, so no recorded change can name it.