List product custom fields

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

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

const { data: customFields } = await client.products.customFields.list('prod_UkLWZg9DAJ')

{
  "data": [
    {
      "id": "cf_UkLWZg9DAJ",
      "label": "Title",
      "type": "Spree::Metafields::ShortText",
      "field_type": "short_text",
      "key": "custom.title",
      "value": "wool",
      "created_at": "2026-05-21T18:11:32.732Z",
      "updated_at": "2026-05-21T18:11:32.732Z",
      "storefront_visible": true,
      "custom_field_definition_id": "cfdef_UkLWZg9DAJ"
    }
  ],
  "meta": {
    "page": 1,
    "limit": 25,
    "count": 1,
    "pages": 1,
    "from": 1,
    "to": 1,
    "in": 1,
    "previous": null,
    "next": null
  }
}