A new period or a revision in a series an alert follows

postWebhookseriesChange

Headers

webhook-idstring required

evt_<change id>, the same on every retry: deduplicate on it.

webhook-timestampstring required

Unix seconds when the message was signed. Refuse values more than 5 minutes from your clock.

webhook-signaturestring required

v1,<base64 HMAC-SHA256 of id.timestamp.body under the base64-decoded whsec_ secret>. Space separated when several.

Payload

type'series.new_period' | 'series.revision' | 'alert.test' required
timestampstring date-time required
dataobject required

One list_changes entry: {id, type, created_at, indicator, place, frequency, period_count, first_period, last_period, changes, source, links}.

Response

Any 2xx acknowledges the message. Other answers, timeouts (5 s) and redirects are retried with backoff.

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.