faq Someone asks whether Jev is ‘just another chat LLM’ or JSON-mode wrapper. Updated Sep 20, 2026
Is Jev an LLM?
No. Jev is a System One decision model: structured answers, not chat text generation.
No. Jev is TypeSafe’s System One decision model. You send state and typed questions; you get structured answers your code can consume. It is not a chat product and not “JSON mode on an LLM.”
LLMs optimize for generating text for humans. System One optimizes for calibrated decisions software can branch on.