Yes I would consider the search string as a kind of api, just like bang sequences in DuckDuckGo. I think of an api as anything where you send input to a service

Yes I would consider the search string as a kind of api, just like bang sequences in DuckDuckGo. I think of an api as anything where you send input to a service that is validated against a syntax of some sort and affects the execution of the program. It’s a broad definition. Why wouldn’t you as a user expect that the search strings be portable across accounts? It would be surprising, especially if the changes across locales was small such as the one in this article. I have copied and pasted filters from blogs on the web for example to get some more complex queries. It’s not like you get a lot of feedback from gmail if you get it “wrong”. Your comments on naming are on target and that’s why we end up with ugly guids across Windows, for example. I mean who wouldn’t know that your trash folder is really {4f342ebb-d392-4a7d-8db8-3f718c1bcd71}. But that would make for an entirely unusable experience for 100% of users. I would assume that, just like a programming language, “trash” is a reserved word and you can’t use it for the name of your own tags. I have not tried it though. This is ultimately a subjective decision to make. I’ve done this hundreds of times when designing APIs. Balance usability across multiple user bases and maintain compatibility with decisions that I’m sure were made decades ago when gmail was a beta project in the early 2000s. It’s a problem with no “right” answer, so I think having a guiding principle - such as prioritizing consistency - can make those decisions easier and result in a more sane api.