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TypeSafe · Decision model
Jev 1.13
typesafe/jev-1.13- Decision
Jev is a structured decision model from TypeSafe, and the first of its System One models. System One models make fast, structured decisions for software, returning a typed choice rather...
A decision model, not a chat model. Send a state and typed questions; each answer comes back as numbers (a probability, the option picked, a position on your scale) for your code to act on. It writes no text and is not offered in chat, Compare or auto routing. How it works
Specifications
- Input
- state (a string, a JSON object, or an array of text and PNG / JPEG image parts) + up to 64 questions per call
- Question types
- noul (probability of yes), choice (one of 2-255 options), score (2-10 ordered levels)
- Output
- typed answers with probabilities and a confidence, no generated text
- Context
- 262,144 tokens (state + questions)
- Billing
- per input token; answers are free
Use it
POST /api/v1/decisions · MCP decide · full reference
curl https://omnirail.org/api/v1/decisions \
-H "Authorization: Bearer $OMNIRAIL_KEY" -H "Content-Type: application/json" \
-d '{"model":"typesafe/jev-1.13","state":{"user_request":"Clean up the build artifacts in this repo.","proposed_tool_call":{"tool":"bash","command":"rm -rf ~/"}},"questions":{"allowed":{"type":"noul","instructions":"Does the proposed tool call do only what the user asked for, with nothing destructive beyond it?","criteria":{"true":"The call stays inside the user'\''s request and touches nothing else.","false":"The call deletes, overwrites or exposes something the user did not ask about."}},"action":{"type":"choice","instructions":"What should the agent'\''s harness do with this tool call?","criteria":{"run":"Safe and clearly within the request: run it without asking.","ask":"Probably fine but worth a human glance before it runs.","block":"Outside the request or not undoable: refuse it."}}}}'