If the attributes of the product you wish to list meet either Condition 1 or Condition 2 in the category metadata API, they are required purchase options.
Condition 1: Attributes that satisfy the following parameter values:
“required": “MANDATORY”
“groupNumber": “NONE”
“exposed": “EXPOSED”
Condition 2: Attributes for which you need to select and enter one of the following parameter values (group attribute):
“required": “ MANDATORY”
“groupNumber": “1”
“exposed": “EXPOSED”
In the category metadata API, you can check the available values for each required purchase option:
The “dataType” field indicates what data types can be entered (NUMBER, SELECT, STRING, etc.)
The “usableUnits” field indicates the attribute unit values that can be entered (kg, g, count, set, etc.)