What it is
A local browser playground for TypeSafe's Jev decision model, accessed through OpenRouter. It is for developers who want to experiment with Jev's typed questions without waiting for a TypeSafe invitation. Python standard library only.
How it uses Jev
Jev makes decisions based on a state and typed questions (Choice, Score, Noul). The playground sends these to OpenRouter and displays the returned calibrated probabilities. The README does not specify how the result is used in code beyond the playground interface.
Primitives:choicescorenoul
Technique worth stealing
Validating OpenRouter's rejection of null for instructions, score levels, and noul true/false before sending.
Try it
Set OPENROUTER_API_KEY, run python3 server.py, open http://127.0.0.1:3001.
Evidence
Each line is one question put to Jev about the README. ≥ 0.60 reads as yes, ≤ 0.40 as no; in between Jev is not making a call.
- Jev-centricyes0.78
- Shows a System One patternno0.11
- Handles uncertaintyno0.04
- Measuredno0.03
- Runnableyes0.97
- Worth recommendingno0.15
- Model replicano0.03
- Problem scopescore on a 0–2 scale0.45
- About Jevyes0.97
Signals by Jev jev-1.13.0, card written by DeepSeek V4.1 Flash from the README on 20 Sept 2026.