Jev vs OpenAI
OpenAI Structured Outputs makes a chat model return JSON that matches a schema. Jev answers choice, score and yes/no questions and returns a probability for each option.
Different jobs
A JSON schema says what shape the text should have. Jev says which decision you are asking and which answers are allowed. Structured Outputs fits when you need a custom object, extracted fields, or generated text that still parses. Jev fits when the next line of your program is a branch.
What comes back
On a choice or a score, Jev returns the selected option, a probability for every option, and a confidence value. A yes/no question returns the probability of yes. A schema does not add those signals. A chat model can be asked to invent a confidence number, but that number is not a probability over the options you declared.
Using both
Generate or extract with a language model, then ask Jev the narrow question before the code acts. Do not treat either output as a legal or medical decision. Set your own threshold and keep a person on the high-stakes path.