Jev

The pieces, in reading order

1. Part 1

   Jev, the AI that can't write: where it saves money and where it's hype

   What Jev is in plain English, whether it's secretly an LLM, what TypeSafe still hasn't published, and where it genuinely saves money. One independent paper sent Jev 346,009 requests for under $10. Plus five questions to decide whether it would pay for you.

2. Part 2

   Jev, the AI at a fiftieth of OpenAI's price: is it any good?

   Jev is a new AI model that costs a fiftieth of the price of OpenAI's GPT-5.4. On my first test it beat GPT-5.4 by 11 points, and I told the internet. Two days later I ran the same test again, and the win was gone.

3. Part 3

   Jev is not an LLM. On the hard half it beat GPT-5.4, Gemini 3.1 Pro and Sonnet 5, at a fiftieth of the cost.

   Jev does not generate text. You give it a question with defined answers and it hands back one of them plus a probability. On 42 citation checks it tied the…

4. Part 4

   GPT-5.4 beats Jev on a confidence threshold, once tested at its own values.

   I published a wrong finding last week: that GPT-5.4's confidence score has no usable threshold. It does, and swept over its own values it beats Jev at every…

5. Part 5

   Paying your AI to think longer didn't fix its mistakes. It cost up to 4.2x more.

   I gave three AI models room to think before answering, the fix everyone assumes will work. None got more reliable. It cost 2.4 to 4.2 times more per answer to find that out, and Jev, the cheap specialist model, still caught more of the mistakes.

6. Part 6

   I said Jev beat GPT-5.4. Five reruns can't tell them apart, at a fiftieth of the cost.

   I published that Jev, TypeSafe's new model, beat GPT-5.4 by 11.1 points on hard fact-checks. Rerun five times, the two can't be told apart, Jev costs a fiftieth as much, and it lets more wrong claims through. Plus the five-run check.

7. Part 7

   Jev, a cheap AI, did two thirds of my filing: same result as Claude, 63% cheaper

   Jev, a cheap AI, handled two thirds of my filing and passed the rest to Claude. Same result as Claude alone, 63% cheaper. The catch: the hand-off isn't a check, because Claude makes the same mistakes.

8. Part 8

   Jev is a narrow tool with four clear uses. Greg Isenberg's $10m framing is not one of them.

   Greg Isenberg's episode on Jev promised $10m businesses. His own guest says use it for routing and keep it away from your money. Here is each claim against the data, and the four conditions under which the tool earns its place.