This will allow you to create a custom field that can be used to gather custom info related to a Lead.

POSTcustom_field_identifier *string
POSTcustom_field_type*Posible values are 'input_field', 'text_area', 'drop_down', 'radio_button', 'checkbox'
POSTcustom_field_options **array of arrays with one parameter: option_name (string containing the name of the option)

* Required fields ** Required for drop_down, radio_button, checkbox field types. Here is an example:

'actions' => [
    '0' => [
        'cmd' => 'create_custom_field',
        'custom_field_identifier' => 'Custom field name',
        'custom_field_type' => 'drop_down',
        'custom_field_options' => [
            '0' => ['option_name' => 'blue'],
            '1' => ['option_name' => 'brown']

Success message:

  "status": "Success",
  "message": "Custom Field created",
  "type: "114"

Error Cases:

Type NumberMessageCause
263Custom Field name can only contain letters, numbers, dashes or underscores
  • custom_field_identifier can only contain letters, numbers, dashes or underscores.
264Custom Field already exists or not allowed
  • custom_field_identifier value already exists in the database or is not allowed.
265Custom Field cannot be empty
  • custom_field_identifier must not be an empty string.
269Custom Field type not valid
  • custom_field_type value is not one of 'input_field', 'text_area', 'drop_down', 'radio_button', 'checkbox'.
270Options not an array
  • custom_field_options needs to be an array.
272Option cannot be empty
  • option_name must not be empty.
273Options must have two or more elements
  • custom_field_options has to be an array with at least two elements for the options.
An example of an error message:
  "status": "Error",
  "message": "Custom Field name can only contain letters, numbers, dashes or underscores",
  "type": "263"