Create shipment custom field

POST /api/v2/shipments/{shipment_id}/custom_fields

cURL

cURL

curl --request POST \
  --url https://api.example.com/api/v2/shipments/{shipment_id}/custom_fields

Creates or updates a custom field on a shipment. If a custom field with the specified api_slug already exists, it will be updated.

Path parameters

Parameter	Required	Description
shipment_id	Yes	The ID of the shipment

Request body

Parameter	Required	Description
api_slug	Yes	The slug of the custom field definition
value	Yes	The value to set (type depends on the definition’s data type)

Authorization

Requires update permission on the shipment.

Response

Returns 201 Created with the custom field resource on success.

Behavior

• Uses find_or_initialize_by internally, so it creates if missing or updates if it exists
• Values are validated against the definition’s data type
• For enum fields, values are validated against the definition’s options