BOOLEAN PROBABILITY
Noul
Ask whether a statement is true. Receive a number from 0 to 1 instead of a brittle yes/no string.
is_urgent: 0.92
DECISION MODEL · API ACCESS IN PROGRESS
Meet Jev.
Fast, typed decisions for software. Send state, define the possible outcomes, and get probabilities your code can act on.
BeatAPI integration is being verified. No live access is claimed yet.
jev / decision42 ms
QUESTION
Which action should the agent take next?
ask_user0.91
continue0.06
stop0.03
03decision primitives
255choice options supported
1→Nquestions per state
JSONsoftware-ready output
NoulChoiceScoreRoutingGuardrailsVerification
01 / MODEL
WHAT IS JEV?
Not another model that
writes more words.
Jev turns messy application state into bounded decisions. Your code defines what answers are legal. Jev evaluates them in parallel and returns the selected answer, probability distribution, and confidence signal.
Read the complete explanationFINITE OPTIONS
Choice
Select one option from a set and keep the complete distribution for thresholds, fallback, and review.
queue: "technical"
ORDERED RUBRIC
Score
Evaluate an ordered scale, preserve uncertainty across levels, and branch with more nuance than labels.
risk: 1.64 / 2
02 / REQUEST
INTERACTIVE BUILDER
Shape a Jev request.
Before you ship it.
Choose a primitive, describe the state, and generate a clean request payload. Nothing is sent from this page.
Request shapeReady to copy
03 / CONTROL
HOW IT FITS
Jev decides.
Your code remains in control.
Keep permissions, thresholds, retries, logs, and side effects in deterministic code. Use Jev for the bounded judgment in the middle.
01STATE
→
Events, text, tool history, or structured application context.
02JEV
→
Evaluate Noul, Choice, and Score questions in one request.
03CODE
Apply thresholds, validate, branch, log, or escalate to review.
USE CASES
Small decisions.
Serious leverage.
Jev works best when the possible outcomes are known, the decision repeats often, and your software needs a probability—not another paragraph.
01↗
02↗
AGENT SYSTEMS
Route the next tool or subagent
Choice · Tool history → next actionSAFETY
Gate risky actions with thresholds
Noul · Proposed action → allow / review03→
OPERATIONS
Score urgency and route support
Score + Choice · Ticket → queue04→
QUALITY
Verify outputs before they ship
Noul · Output + criteria → retryJEV VS LLMS
Decision primitive,
not prose generator.
Use both models for what they are shaped to do. Jev narrows uncertainty inside code; LLMs produce open-ended language, reasoning, and artifacts.
See the full comparison ↗OUTPUTJEVLLM
ShapeTyped valueGenerated text
OutcomesDefined firstOpen-ended
UncertaintyProbabilitiesOften inferred
Best roleDecideCreate
FIELD GUIDE · 18 PATTERNS
What can you
actually build?
See concrete patterns for agent verification, LLM evaluation, routing, RAG filtering, reranking, support operations, guardrails, and structured extraction—plus the cases where rules or an LLM are the better choice.
Explore the complete use-case guide
01Agent completion verifier
02LLM-as-a-judge alternative
03RAG evidence filter
04Tool and model router
05Confidence-gated workflow
06Semantic policy check
FAQ
Questions,
decided.
The essential facts about Jev API access, decision primitives, production use, and this independent guide.
01What is Jev?
Jev is a decision model for software. It reads text or structured state, evaluates questions you define, and returns typed answers with probabilities instead of writing an open-ended chat response.
02Is Jev a chatbot or a general-purpose LLM?
No. Jev is designed for bounded decisions inside software: choosing an option, estimating a yes-or-no probability, or scoring an ordered scale. Use a language model when you need prose, code, or open-ended generation.
03What are Noul, Choice, and Score?
Noul returns a probability for a yes-or-no statement. Choice selects among named options and returns the probability distribution. Score evaluates an ordered rubric and returns a probability-weighted position.
04Who created Jev?
Jev is developed by TypeSafe AI as its first System One model. jevapi.io is an independent developer resource and is not the official Jev website.
05Is this the same Jev as the YouTube creator FaZe Jev?
No. This site covers the Jev decision model used in software. It is unrelated to the creator and streamer known as FaZe Jev.
06Can I call Jev through BeatAPI today?
The BeatAPI integration is currently in progress. This site will publish the verified model ID, endpoint, pricing, and runnable examples only after an authenticated request, response, usage record, and task log have been checked end to end.
07What should Jev be used for?
Strong fits include agent routing, support triage, risk scoring, tool selection, output verification, guardrails, and other high-volume decisions where the possible outcomes are known in advance.
08What is a System One model?
TypeSafe uses the term for models that make a fast, direct judgment over options you declare instead of writing an open-ended answer one token at a time. Jev is TypeSafe AI’s first System One model. See Jev vs LLMs for how the interfaces differ in practice.
09What does the Jev API cost?
For the direct TypeSafe API, the current model specifications list $0.042 per million input tokens and free output tokens (checked September 20, 2026). BeatAPI pricing is not published here yet; it will appear only after the integration is verified end to end. Details are in the API guide.
10Does Jev work in languages other than English?
Jev accepts text only. TypeSafe documents English as the primary training language and where accuracy is currently best; other languages are handled but not equally well. Test your own language and domain before relying on a threshold.
11Does a confidence score guarantee correctness?
No. Confidence is a signal, not proof. Production systems should set thresholds, validate outcomes, log model versions, and route uncertain or high-impact cases to human review.
INTEGRATION IN PROGRESS
Make the decision.
Keep the control.
BeatAPI access will open here after the model, billing, and usage path are verified end to end.