Webhook

shipments.parcel_updated

The seller changed a shipment's parcel weight or dimensions. Requires read:shipments.

Headers

webhook-id
Type: stringFormat: uuid
required

Unique ID of the event. Retries of a delivery send the same ID, so use it to deduplicate.
webhook-timestamp
Type: integerFormat: int64
required

When this delivery attempt was sent, as a Unix timestamp in seconds. Each retry sends a new timestamp.
webhook-signature
Type: string
required

Space-separated signatures, each v1, followed by the base64 HMAC-SHA256 of {webhook-id}.{webhook-timestamp}.{body}, keyed with your webhook secret.

Body·ShipmentParcelUpdatedWebhookBody

required

application/json

data
Type: ShipmentParcelData
required

The event's data. Its shape depends on the topic.

Properties: 6
seller_id
Type: string
required

The ID of the seller the event belongs to.
timestamp
Type: stringFormat: date-time
required

When the event happened, in ISO 8601. Stable across retries; the webhook-timestamp header is when each attempt was sent.
type
const:
shipments.parcel_updated
required

The webhook topic.
version
const:
v2
required

The payload version.

Responses

200

Acknowledge delivery. Any 2XX status counts.
default

Fail delivery. Non-2XX statuses and timeouts are retried.

postshipments.parcel_updated

{
  "type": "shipments.parcel_updated",
  "timestamp": "2026-10-20T16:00:00.123Z",
  "data": {
    "shipment_id": "",
    "weight": {
      "value": 1,
      "unit": "ounce"
    },
    "dimensions": {
      "length": 1,
      "width": 1,
      "height": 1,
      "unit": "inch"
    },
    "hazardous_material": "not_hazardous",
    "signature_required": true,
    "insurance": {
      "amount": {
        "amount": "",
        "currency": ""
      },
      "contents": ""
    }
  },
  "version": "v2",
  "seller_id": "1234567"
}

No Body

Acknowledge delivery. Any 2XX status counts.

shipments.tracking_code_added

shipments.items.added