Builder Nate Herkelman just shared a test of the Jev AI model, which is built for structured outputs like yes/no, categories and scores. He reports processing 1,000 emails against seven decision rules in 70 seconds for just $0.09 For comparison he notes the same task took about five minutes using Luna. My take is that models like this aren't for the main conversational loop. Their value is as a fast, cheap pre-processing or routing layer. For a law firm intake agent, the first step is always classification: is this an existing client? Is it a new lead? What practice area does it fall into? You could burn a lot of money and latency having GPT-4o figure that out. Or, you could have a model like Jev do that initial classification instantly and for a fraction of a cent per query. Then you pass the categorized request to the expensive, heavyweight model. This splits the logic cleanly and optimizes cost Herkelman also described a six-step process for "Codex skills," which he calls "a recipe for your agent" to capture processes and examples This sounds like a solid framework for building more reliable, repeatable system prompts and tool definitions instead of just tweaking them endlessly. The big unknown is the complexity of the task Jev actually performed. The post doesn't detail the seven decision rules from the email test, so we can't tell if it was simple keyword spotting or something requiring more nuance Until we see the actual rules or a similar example, it's hard to know where the line is for using a specialized model like this in a client build.