how to setup and use Jev in 10 minutes from nothing to a call that returns a decision 1. get access join the waitlist at typesafe, people report getting in within a day don't want to wait, it's already hosted in two places: → vercel ai gateway as typesafe-ai/jev, no waitlist → cloudflare workers ai as typesafe/jev 2. install the skill so your agent writes the call correctly npx skills add typesafe-ai/skills --skill typesafe-ai on claude code it's two commands: - claude plugin marketplace add typesafe-ai/skills - claude plugin install typesafe@typesafe-ai then in your prompt just say "use the typesafe skill" 3. learn the shape before you write a line the body is a state and a map of questions. the state is your context, whatever you would have pasted into a prompt. the questions are typed three types, that's the entire api: → Noul returns a raw 0 to 1 → Choice picks one from up to 255 options you define → Score places it on a 2 to 10 level scale every Choice and Score comes back with a confidence from 0 to 1 4. make the first call a real one pick a decision already living in your code as an llm call that never writes text. the "which of these" one how to do it: - build the option list in your own code, not in the prompt - send your existing context as the state, unchanged. don't rewrite it yet - ask your question plus three more you're curious about, they run in parallel against the same state and output tokens are free - log the answer, the confidence, and what your old call said - leave the old call running. delete nothing on day one 5. put a limit on it before it touches anything read confidence on every response, never just the answer low limit for reading and sorting. 0.85+ for anything you cannot undo. everything under the limit falls through to the old call that fallback is four lines, and it's the reason you can ship this on a tuesday instead of planning it for q4 the 10 minutes is real. the hour after is the actual work: you, a log of answers and confidences, deciding where your lines go start in the playground in the console, and paste a real state from your own product, not the sample one