Unique code of courier. Get the slugs from here.
Name of courier
Contact phone number of courier
Other name of courier
Website link of courier
The extra fields need for tracking, such as
The extra fields which are optional for tracking. Basically it's the same as required_fields, but the difference is that only some of the tracking numbers require these fields.
Default language of tracking results
Other supported languages
Country code (ISO Alpha-3) where the courier provides service