Looking at previous discussions it would appear that there is no list of valid tracking companies. However the documentation indicates that there is such a list
If you are creating a fulfillment for a supported carrier, you can simply send the
tracking_numbersand Shopify will generate the
tracking_urlfor you. If creating a fulfillment for an unsupported carrier (not in the
tracking_companylist) send the
Should I believe the documentation or should I believe previous discussions on this issue ? ( I don't know which is most recent. The previous questions or the documentation)
Maybe I am asking the wrong question. Is there a list of "supported carrier"s ?
For anyone else who finds this. Go to this page and scroll down slowly from the top. You will shortly find the list. I missed this and was also annoyed to find there is no direct link to this list. https://shopify.dev/docs/admin-api/rest/reference/shipping-and-fulfillment/fulfillment