const options = {
  method: 'GET',
  headers: {'x-spree-api-key': '<api-key>', Authorization: 'Bearer <token>'}
};

fetch('http://{defaultHost}/api/v3/admin/product_types/{id}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

curl --request GET \
  --url http://{defaultHost}/api/v3/admin/product_types/{id} \
  --header 'Authorization: Bearer <token>' \
  --header 'x-spree-api-key: <api-key>'

{
  "id": "pt_UkLWZg9DAJ",
  "name": "T-Shirt",
  "products_count": 0,
  "created_at": "2026-01-15T12:00:00.000Z",
  "updated_at": "2026-01-15T12:00:00.000Z",
  "delivery_profile_id": null,
  "option_type_ids": [],
  "category_ids": [],
  "custom_field_definitions": []
}

{
  "error": {
    "code": "record_not_found",
    "message": "Product type not found"
  }
}