This seems like I missed something very basic, but Postman appears to use the term and type of Query for all GraphQL operations
Typically, a a query is a read operation, and a mutation is create/update. (screenshot from Insomnia to show how an endpoint and appears there -we are using Postman for automated testing). I’ve done a bunch of successful query tests with Postman. The Query tab of Insomnia (when clicked on) just shows the URL.
In Postman, when I try to send the mutation shown in Insomnia, I get an error that says
“message”: “Cannot query field "createThing" on type "Mutation".”
I wasn’t really trying to query per se, and the mutation works in Insomnia. Is there another setting one needs to tweak for mutations to work in Postman?