A value is required for the field

A value is required for the "age_range_description" field.

This error means that you need to provide the mentioned attributes for your product. It is relevant when you create new products through Creation Profiles in Salestio. It means that these fields are required to list this type of product on Amazon. Other required fields might be 'bottoms_size_system', 'target_gender', 'material_type', 'gemstone_type' depending on your product type.