Update a shipment

import { createAdminClient } from '@spree/admin-sdk'

const client = createAdminClient({
  baseUrl: 'https://your-store.com',
  secretKey: 'sk_xxx',
})

const fulfillment = await client.orders.fulfillments.update('or_UkLWZg9DAJ', 'ful_UkLWZg9DAJ', {
  tracking: '1Z999AA10123456784',
})

{
  "id": "ful_UkLWZg9DAJ",
  "number": "H63964573474",
  "tracking": "1Z999AA10123456784",
  "tracking_url": "https://wwwapps.ups.com/WebTracking/track?track=yes&trackNums=1Z999AA10123456784",
  "cost": "10.0",
  "display_cost": "$10.00",
  "total": "10.0",
  "display_total": "$10.00",
  "discount_total": "0.0",
  "display_discount_total": "$0.00",
  "additional_tax_total": "0.0",
  "display_additional_tax_total": "$0.00",
  "included_tax_total": "0.0",
  "display_included_tax_total": "$0.00",
  "tax_total": "0.0",
  "display_tax_total": "$0.00",
  "status": "ready",
  "fulfillment_type": "shipping",
  "fulfilled_at": null,
  "items": [
    {
      "item_id": "li_UkLWZg9DAJ",
      "variant_id": "variant_UkLWZg9DAJ",
      "quantity": 1
    }
  ],
  "metadata": {},
  "adjustment_total": "0.0",
  "pre_tax_amount": "0.0",
  "created_at": "2026-06-17T13:37:06.154Z",
  "updated_at": "2026-06-17T13:37:06.499Z",
  "order_id": "or_UkLWZg9DAJ",
  "stock_location_id": "sloc_UkLWZg9DAJ"
}