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What Is Jev

Independent research repository on Jev: sourced findings that separate verified claims from vendor marketing repeated by others, a rubric-scored catalog of public Jev repositories, and recurring design patterns with evidence.

Stars
1
Language
Python
Published by
Community
Author
g0runmezadam
Last verified
Oct 2026

About this project

A sourced, critical research file on Jev — TypeSafe AI's "System One" decision model — plus a rubric-scored map of what people are actually building with it. Jev does not write text. You give it a state and typed questions (choice, score, noul = yes/no); it returns probabilities. That makes it cheap, fast and easy to wire into software — and also easy to over-sell. This repository tries to answer three questions with evidence instead of enthusiasm:

Quoted from the project's README. Read the full README.

Highlights

  • A five-rank source trust order, with secondary summaries including AI-generated ones explicitly excluded as evidence.
  • Every entry links to its source; the repository gives links and assessments rather than republishing third-party content.
  • Repository scores come from a written rubric with a second pass on the top class, and star counts never affect a score.
  • Machine-readable data in data/repos.jsonl plus generated category pages, with a full Turkish version built from the same data.

Watch out

Scores are an LLM's judgment against a written rubric rather than benchmarks of the projects themselves, and for most repositories the author read the description, metadata and the first 12,000 characters of the README instead of the code. "Calls Jev" only means the README or code shows a real call, and the jev GitHub topic is free-form, so many tagged repositories are unrelated and get marked as such rather than dropped. The README also notes that Jev is not deterministic call to call and that vendor accuracy figures measure agreement with judge models, not ground truth. Entries for deleted repositories are kept and marked gone. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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From the Jev guides

Original write-ups on what this entry is for.

Most Jev accuracy problems are state problems. What belongs in a state, what is a pre-made judgment to leave out, and why naming the slice you ask about matters more than the wording.
Jev Practices & Patterns#state#design#primitives
Read article
A Noul returns one number and no separate confidence. How to read the value, pin its boundary with criteria, split compound questions, and set a per-action threshold that matches the cost of being wrong.
Jev Practices & Patterns#noul#primitives#confidence
Read article
A Score is a weighted position, not a ruler. Why the number can land between levels, why levels are judged separately, and how to combine several atomic scores in code instead of one crowded rubric.
Jev Practices & Patterns#score#primitives#scoring
Read article
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