{
  "name": "frequent_buyer",
  "label": "Frequent Buyer",
  "type": "customer",
  "active": true,
  "data": {
    "type": "boolean"
  },
  "_links": {
    "self": {
      "href": "/api/v2/custom_fields/1",
      "class": "custom_field"
    }
  }
}