A checkout session was updated (versioned lifecycle contract)

RECEIVEserving.checkout.updated

Message

event_versionstringrequired

Semver of this event contract. Starts at "1.0"; bump on a breaking payload change.

event_idstringrequired

Fresh per emission — a ULID prefixed "evt_", lexicographically sortable by emission time.

matches ^evt_[0-9A-HJKMNP-TV-Z]{26}$

occurred_atstring<date-time>required

merchant_idstringrequired

store_idstringrequired

surfacestringrequired

Best-effort Google surface, derived from the UCP-Agent header's profile-URL host. "unknown" when the header is absent or doesn't recognizably match a known Google surface.

Allowed:google_ai_modegoogle_geminiunknown

checkout_idstring

Absent on serving.request.telemetry_recorded; the Sarvex checkout session id everywhere else.

Headers

message_idstringrequired

Unique per message; consumers de-duplicate on this.

ordering_keystringrequired

The store_id. Guarantees per-store ordering; the catalog/serving tenant boundary (a store belongs to one merchant — see architecture §2a).

occurred_atstring<date-time>required

sequenceinteger<int64>

Monotonic per-connector sequence carried from the origin signal (ingest events only).

trace_idstring

Correlates a chain of events from one originating cause.

schema_versionstringrequired

Try it

Server

ServerCustom server URLOverrides the selected server; the channel address is appended.

Payload

Message payload

Live sending isn't possible for pubsub from a browser tab — copy the sample above and run it against your broker.

Message

{
  "event_version": "1.0",
  "event_id": "string",
  "occurred_at": "2019-08-24T14:15:22Z",
  "merchant_id": "string",
  "store_id": "string",
  "surface": "google_ai_mode",
  "checkout_id": "string"
}