curl --request POST \
  --url 'https://api.flashcat.cloud/field/create?app_key=' \
  --header 'Content-Type: application/json' \
  --data '
{
  "field_name": "<string>",
  "display_name": "<string>",
  "field_type": "text",
  "value_type": "string",
  "description": "<string>",
  "options": [
    "<string>"
  ],
  "default_value": "<string>"
}
'

{
  "error": {
    "code": "<string>",
    "message": "<string>"
  },
  "data": {
    "field_id": "<string>",
    "field_name": "<string>"
  }
}