I guess it comes from the `tagsExhaustive` keyword. But I tried to search what it does in the documentation, and it doesn't return any hit. I then searched in the git repository and found it in some examples and CLAUDE.md but it doesn't really seem straightforward.
Perhaps it makes sense for AI agents, but as a human, I will pass.
The whole setup reminded me of the mess people would make with RxJS, and this comment chain seems to indicate it's got the same drawbacks.