JEV AI · A BEGINNER PATH

Learn Jev AI from zero

Start with what Jev does, make your first typed decision, then learn when to use Choice, Score, or Noul in a real workflow.

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CHOICE / ROUTEEXAMPLE
“Where should this request go?”
technical0.82
billing0.11
human0.07
TOP OPTIONtechnicalillustrative values

Jev is TypeSafe AI's first public System One Model. typesafe-ai/jev returns Choice, Score, and Noul answers with probabilities; high confidence can suggest action, while low confidence routes to review.

01 / DEFINITION

What is TypeSafe Jev?

TypeSafe Jev is a System One model for software judgment tasks. Instead of generating free-form text, it returns typed Choice, Score, or Noul answers to questions you declare, together with probabilities or confidence signals.

[1] TypeSafe introduction ↗
02 / MECHANISM

How does Jev work?

An application puts decision evidence in state and defines bounded questions with explicit criteria. Jev returns structured distributions; application code then validates the answer, applies thresholds, and chooses automation, human review, or abstention.

[2] TypeSafe question primitives ↗
START HERE

From the concept to a reliable first call

00 Continuous Jev developer guide Follow one path from the core concept to the official SDK and LangChain. 01 What is Jev? Understand System One, typed outputs, and when the model fits. 02 Complete TypeSafe Jev tutorial Go from task fit and the first call to confidence policy and production checks. 03 Your first Jev API request Understand the request, response, and safe fallback with cURL. 04 Jev Python SDK tutorial Install typesafe-sdk, send a request, and consume the result safely. 05 Choice, Score, and Noul Choose the right question type for each decision boundary. 06 Jev confidence thresholds Control automation with risk bands, calibration data, and human review. 07 Jev Git workflow tutorial Apply commit classification, pull-request risk, and CI gates to a real development workflow. 08 Browse open-source Jev projects Inspect real repositories for browser automation, routing, compaction, safety, and evaluation.
FEATURED / 01 JEV AGENT ENGINEERING · 22 MIN Separate Agent decisions from LLM generation From a fast decision layer to context compaction: separate generation, judgment, execution, and fallback. READ THE GUIDE
COMMUNITY EVIDENCE / SOURCE REVIEW

How public projects use Jev

This is not a testimonial wall for this site. Every card points to a public repository, separates reviewed implementation facts from outcomes we have not independently tested, and links to the evidence.

E2 / SOURCE REVIEWED 2026-09-26

01jev-git

A Rust Git semantic gate that runs as pre-commit and pre-push hooks. It reads a staged or piped diff and asks two Jev Noul questions about exposed credentials and destructive payloads; it is neither a code generator nor a conventional syntax linter.

REVIEW BOUNDARY

README, Rust implementation, and tests at pinned commit d1b6732 were reviewed on 2026-09-26. This site did not run the binary or measure latency. README claims such as about 80 ms and a sub-2 MB static binary are author-reported, not independent benchmarks.

E2 / SOURCE REVIEWED 2026-09-19

02jev-trader

A market-making experiment on Kuru’s MON-USDC book on Monad, with optional per-block Jev buy/sell decisions.

REVIEW BOUNDARY

Defaults to a mock model and simulates fills without a wallet key. Live trading, latency and profitability were not verified.

E2 / SOURCE REVIEWED 2026-09-19

03jev-drone

A MuJoCo drone experiment deriving scene features from camera buffers for Jev tactical advice.

REVIEW BOUNDARY

The 2.5/50/500 Hz figures describe the author’s simulation architecture. They are not a flight-safety guarantee or validation on a real aircraft. README and integration source reviewed at a fixed commit; not independently run or benchmarked by this site.

Understand the E0–E3 evidence levels →
COMMUNITY DIRECTORY / 1428 RECORDS See how Jev is being used in the wild. Find Jev repositories, integrations and articles by task, with decision points, reported licenses, activity and source evidence. Open project radar

Quick answers

What is Jev?

Jev is TypeSafe AI's first public System One Model: it returns typed Choice, Score, and Noul answers with probabilities — not free-form prose.

Choice / Score / Noul

Choice picks one named option; Score places state on an ordered rubric; Noul (boolean) estimates P(true). Confidence comes from the option distribution.

When to use a human

Low confidence → human queue with no default action. Money, refunds, and irreversible side effects stay human-owned — suggestions only.

Choice

Pick one named option. Returns the key, full probability map, and confidence.

Score

Place state on an ordered rubric. A level index — not an accuracy promise.

Thresholds

Keep act / confirm / human bands in your code. Calibrate on your labeled data.

FAQ

What is TypeSafe Jev / System One?

Jev is TypeSafe AI's first public System One Model. It returns typed Choice, Score, and Noul answers with probabilities instead of free-form text. Vercel AI Gateway is the access layer demonstrated by this site.

Do I need a self-built API relay?

If you use the Gateway path demonstrated here, your app or serverless function can call it without an extra relay. That does not make Gateway the only way to access Jev.

Does Jev make money or refund decisions?

No. Templates and examples only suggest routes or labels. Money and refund decisions stay with humans or other systems.