What are the useful applications of Jev so far? Not to sound dismissive, I just haven’t seen what people are using it for yet.

Here's a third-party (not Jev) showcase of things people built, which helped me kind of get the appeal. https://bentossell.com/jev/ (not mine).

LLMs can be too creative and often too verbose. Sometimes there is a right answer and a way to get there with the understanding of language, but despite using structured outputs, the model insists on inventing variations not in the schema or coming up with something completely different. A model like Jev that can not do those things, and can give the same output every time with given the same input, and be able to measure probabilities has many use cases.

Lots of use cases! I've personally used it for the following:

1. Evals (once you have your rubric defined and tuned using a reasoning model, jev can be great for running periodic evals especially those that run daily.

2. e-commerce catalog classification 3. quick search using anything as context and query mapping to a pre-defined set.