Good questions! I didn't consider someone would ask if this file is "stateful" or not. I was under the impression that people would already have the impression that yes, you can do stateful things, but it's not the right thing to do so (at least on this use case).

Side-question which I haven't tried yet, do you think VSCode or any other editors could auto-import it as `import * as ProductApi`?

Thank you for your sharing your thoughts. I'll keep that in mind 🎉