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).

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.