jev, typesafe ai's decision model for app logic
About Jev
A hosted model that decides instead of writing. You send it a piece of state and the questions you want answered, and it returns typed answers with a probability on each: Choice picks one option out of up to 255, Score rates against levels you define, Noul answers a yes/no statement. It never returns free text, so there is nothing to parse and no malformed reply to handle. TypeSafe prices input at $0.042 per million tokens and charges nothing for output, which is what makes it usable on every request rather than the expensive ones.
Key Capabilities
Typed answers instead of text: Choice, Score and yes/no, each with a probability, so your code reads a value rather than parsing a reply
Every answer carries a confidence number, so you can act above a threshold and send the rest to a person
$0.042 per million input tokens with output free, cheap enough to run on every request
All your questions go in one call and are answered against the same state, which is where the cost saving actually comes from
Callable from the Vercel AI Gateway, Netlify, OpenRouter and LiteLLM, or straight from the API with the Python or TypeScript SDK
It cannot return an option you did not define, which removes schema and parse failures from that step
Standout Features
Three question types
Choice picks one of up to 255 options, Score rates against your levels, Noul answers a yes/no
Confidence on every answer
A probability you can gate on: act when it is high, hand the rest to a person
One call, many questions
Questions are answered in parallel against one state, so you pay for that state once
Perfect for
Pricing
How much does Jev cost?
Usage-based, no monthly fee · $0.042 per million input tokens · output tokens free · enterprise tier adds higher rate limits and zero data retention
Our Take on Jev
“Jev is worth reaching for when your app keeps asking an expensive model a cheap question: which bucket is this, is this safe to run, how urgent is it. It answers in milliseconds for a fraction of a cent and hands your code a typed value. It is not a smaller LLM and will not write anything, and a confident answer can still be wrong, so keep the confidence gate and keep arithmetic in code.”
Strengths
- Output tokens are free and input is $0.042 per million, so a decision costs a fraction of a cent
- The answer is always one of the options you defined, so that step cannot come back malformed
- Confidence gives you an honest place to draw the line between automatic and human
- Batching every question into one call is documented at 12.2 times cheaper and 10 times faster than one call per question
- Reachable through gateways you may already use, including Vercel and OpenRouter, without a separate account
Limitations
- It writes nothing: no replies, no summaries, no code, so an LLM still sits next to it
- TypeSafe's own limits page lists twelve things it is bad at, including arithmetic, counting and comparing dates
- Accuracy drops as you send more state, so you have to filter before the call rather than pasting the whole document
- Text only, with English the strongest language and CJK explicitly weaker
- Hosted only, no weights to self-host, and signups were paused for demand within a week of launch
Best for
Not ideal for
Compare Jev
Community Buzz
Jev is now available to everyone. No waitlist. Start using it here:
Jev is built for the decisions that software makes millions of times a day. Its pricing is also tuned for that: - $0.042 per million input tokens, output tokens free - Answers in 70 to 500 ms end to end - On TypeSafe's published workflows, up to 190x faster and 440x cheaper than…
We tested Jev against LLM judges on accuracy, repeatability, latency, and cost to see whether System One models could offer a new approach to agent evaluation.
Text classification in MotherDuck just got ~50x faster at ~1% of the cost. prompt_jev() is a SQL function powered by Jev, TypeSafe's new system one model. 100k rows: 40s, $0.50, frontier-LLM accuracy. The LLM took 32 min and $37. Read on: pic.twitter.com/CdP1q8OwDe
The bookkeeping services industry is dead. This weekend, I built a better solution using Jev from @typesafeai. I fed it 34 months of work a firm charged $20,000+ for. Jev did a better job in 20 seconds, for just $0.32 🤯 pic.twitter.com/8lA9h32eOo
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