Events — GET /v1/events — Commerce Census

Events

Six event types, signed on delivery and replayable by cursor. Every consumer eventually needs to backfill a gap.

GET /v1/events

Request

Name	Type	Notes
after	string	Cursor from a previous page.
type	string[]	Filter to the events you act on.

Request & response

POST https://you.example/hooks/price
webhook-id:        evt_01JQ8Z3M4K    // idempotency key — dedupe on this
webhook-timestamp: 1789012345
webhook-signature: v1,K5f9r…         // HMAC over id.timestamp.body

{ "type": "price.changed", "seller": "bestbuy",
  "previous": { "price_minor": 31999 },
  "current":  { "price_minor": 19800 } }

Notes

price.changed · price.threshold_crossed · availability.changed · seller.changed · policy.violated · match.degraded

At-least-once, never exactly-once. Retry ladder: 1 min, 5 min, 30 min, 2 h, then dead-letter.