Carrier Service - Recognize any consecutive shipping rate estimate call belongs to same order.

[KunalMestri]

Hi

For a third-party carrier service app registered with Shopify, Shopify makes an API call, to third-party carrier service, to get the calculated shipping rates.

In case, where a Shopify order gets fulfilled from more than one location then the number of API calls, made from Shopify for calculated shipping rate, is equal to the number of different fulfillment locations for that order.

How can a third-party carrier service come to know that any two or more consecutive shipping rate calculation API call made from Shopify belongs to the same Shopify order?

Any help would be of great value.