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All Jev AI model resources

Entries for TypeSafe AI's flagship System One model: official docs and SDKs alongside community clients, tools, and write-ups.

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3,991
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11
Official
102
Community
3,889
Source sites
296
Deep dives
3,991

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3991
  • Docs171
  • Repos & sites3148
  • Videos74
  • Posts104
  • Articles412
  • Playgrounds82

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Browse the Jev AI model by category

11 ways into the ecosystem. Each category page leads with its own shortlist of starting points.

All 3991 Jev AI model resources

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SlopCop blog post by Jonathan Ellis, published November 12, 2026, reporting a bakeoff of Jev against Gemini Decisions and OpenAI for classifying GitHub event relevance, the switch to GLiDE from Fastino Labs, and lessons on eval design.
Jev Benchmarks & EvaluationsArticle#evaluation#benchmark#research
Community
Flide is an open-source inference engine for Jev-style decision models that serves the Jev /v1/systemone API. Exact state forking makes it up to 9.5x faster than vLLM and SGLang. It runs on NVIDIA GPUs under Linux or Windows WSL2 and ships precompiled kernels for RTX 40 and 50 series cards.
Jev Tools & CLIs#github#python#local
Community
Community n8n node for Jev by TypeSafe that classifies, routes, and scores text with questions you define. It returns one of your options with a probability per option and a confidence value, so uncertain items can be sent to human review.
Jev Integrations & Adapters#typescript#javascript#routing
Community
v-jev 1.4 is a Jev-style decision model on Hugging Face in 0.8B and 4B sizes, built on Qwen3.5 backbones. It returns probabilities for typed questions in one forward pass and adds value extraction and image decisions.
Jev Models & Reimplementations#open-models#classification#calibration
Community
A JEV decision head and rank-16 LoRA adapter for Qwen/Qwen3.5-9B, trained with AReno. Supports choice, noul, and score questions and is served through SGLang or AReno at /v1/systemone. Base weights are not included.
Jev Models & Reimplementations#open-models#local#sdk
Community
A 7.7M-parameter decision model on Hugging Face that reads text or speech and returns one probability per option for choice, score, and noul questions. Speech runs through femto-asr, giving a 10.1M-parameter spoken pipeline.
Jev Models & Reimplementations#open-models#classification#local
Community
1GitHub stars
An autonomous research agent that searches grant sources daily, scores each lead's fit with Jev, and emails one ranked HTML digest with deadlines, amounts, and apply links. Python runs the loop; Composio supplies the search, page-fetch, and Gmail tools.
Jev Agents & MCP#agents#madewithjev#python
Official TypeSafe cookbook that finds a half-remembered film among 5,000 by running one Noul question per film, re-reading the top 80 with longer plots, and putting the top 20 into a single Choice question.
Jev CookbooksDocs#python#benchmark#classification
Community
A five-notebook Jupyter hands-on that runs Jev and Kev, an Apache-2.0 decision model served locally with llama.cpp, over the SMS Spam Collection, comparing accuracy and threshold effects across Kev-4B, 9B, and 27B.
Jev Benchmarks & Evaluations#evaluation#python#local
CodeCut article by Khuyen Tran comparing TypeSafe Jev, RapidFuzz, and Sentence Transformers on the Abt-Buy product matching benchmark, with per-tool merge counts and a walkthrough of asking Jev which product is the same.
Jev Benchmarks & EvaluationsArticle#evaluation#benchmark#classification
Community
npm package that provides TypeSafe AI and Jev bindings for Lion expressions. Published under the @lionlang scope on the npm registry for projects that want typed decisions available inside Lion expressions.
Jev Repos & SDKs#typescript#sdk#community
Community
NestJS module that adds TypeSafe AI decisions to Loopstack workflows. It asks yes/no, choice, and score questions about workflow or agent state and returns probabilities, confidence values, and a legend per answer.
Jev Integrations & Adapters#typescript#sdk#classification
Community
arXiv paper examining numerical nondeterminism in vLLM Split-K LoRA kernels and introducing a deterministic Triton Split-K implementation, measured on GSM8K, MBPP, and Jev-style structured toxicity decisions over Civil Comments.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#calibration
Community
A 1.7B-parameter SocialJev preview model on Hugging Face, fine-tuned from Qwen3-1.7B for typed classification in the social sciences. Runs through Transformers with trust_remote_code or the social-jev package with a vLLM backend, returning a choice and probabilities per query.
Jev Models & Reimplementations#open-models#classification#python
Community
A 4B-parameter SocialJev preview model on Hugging Face, fine-tuned from Qwen3-4B for typed classification in the social sciences. Loads through Transformers with trust_remote_code or the social-jev package with a vLLM backend, returning a choice and probabilities per query.
Jev Models & Reimplementations#open-models#classification#python
Community
0GitHub stars
Unofficial Gleam client for the TypeSafe AI API targeting Erlang, added as a pinned Git dependency rather than published to Hex. It exposes from_env, system_one, typed content and question modules, and Erlang logger integration.
Jev Repos & SDKs#sdk#github#community
0GitHub stars
Swift package with two products: TypeSafeKit, a dependency-free HTTP client for the System One endpoint and model listing, and TypeSafeMiddleware, which adds a DecisionProvider protocol plus route, gate, rate, composite, and evaluate helpers for agent loops.
Jev Repos & SDKs#sdk#agents#routing
Fine-tuned UltraBERT-380M decision model on Hugging Face that scores a state, question, and option list in one forward pass. Uses sigmoid of yes minus no normalized over options; 72.8% dev and 71.9% test accuracy across 13 datasets, with an evidence head documented on the card.
Jev Models & Reimplementations#open-models#arxiv#calibration
Community
A 380M-parameter UltraBERT encoder fine-tuned as a Jev-style decision model: it reads a state, a question, and a list of options and picks one option in a single forward pass. Apache-2.0 weights hosted on Hugging Face, scored by softmax over each option's " yes" logit.
Jev Models & Reimplementations#open-models#python#classification
Community
A Hugging Face checkpoint that fine-tunes UltraBERT-380M into a Jev-style decision model: it reads a state, a question and a list of options and picks one in a single forward pass. Reports 72.6% mean accuracy over 13 datasets on the test split.
Jev Models & Reimplementations#open-models#classification#local
Community
Fine-tuned UltraBERT-380M decision model on Hugging Face that reads a state, question, and option list and picks one option in a single forward pass. Scores options with a square-root softplus of yes minus no, normalized over options; 73.2% dev and 71.9% test accuracy over 13 datasets.
Jev Models & Reimplementations#open-models#arxiv#calibration
Community
arXiv paper presenting AbductionBench, a unified framework and taxonomy for abductive reasoning tasks, instantiated on 27 datasets across ten domains and used to evaluate eight LLMs from four model families on single-choice explanation selection.
Jev Benchmarks & EvaluationsArticle#arxiv#benchmark#evaluation
Community
A Hugging Face model repository for Aster-JEV-27B, a 27B-scale model whose chat template handles text, images, and video, emits tool calls in XML function blocks, and exposes selectable reasoning effort levels.
Jev Models & Reimplementations#open-models#local#agents
Community
Hugging Face dataset holding the scored public predictions, latency timings, and environment for the Aster-JEV-27B vision run: 9,867 of 12,210 requests correct, public index 76.7057, mean 507.2 ms per request on one A800 80GB.
Jev Benchmarks & Evaluations#evaluation#benchmark#open-models
Community
Open, deterministic audit benchmark for System 1 decision models, covering calibration under label-preserving perturbations, cross-question interference, and post-hoc attribution faithfulness across five open-weight models and generative baselines.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#calibration
Community
arXiv paper evaluating 67 systems, including 47 decision models and 20 LLMs, on 43 Arabic tasks across 9 task families under a shared zero-shot protocol. Jev 1.14.0 scores 69.24 against 68.77 for Jev 1.13.0 and 71.81 for Gemma-4-31B.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#benchmark
Community
LoRA adapter set for the Jevvideo long-video frame-selection agent, trained on 8xH200 from OmniJev/OneJev-4B. Ships controller, grounding, and verifier adapters plus per-role metrics and five-benchmark results.
Jev Models & Reimplementations#open-models#video#benchmark
Community
Hugging Face dataset of medical clinical-decision multiple-choice items in Jev request shape, with a clinical_question state and a decision question carrying type, instructions, and criteria. Between 100K and 1M rows across Chinese, English, Japanese, and four more languages.
Jev Benchmarks & Evaluations#evaluation#benchmark#classification
Community
A 46M-parameter Russian and English decision model published on Hugging Face, tagged for classification, NLI, toxicity, moderation, and calibrated distillation. It ships a custom NQ4ForDecision class and a chat template with an optional thinking block.
Jev Models & Reimplementations#open-models#classification#calibration
Community
Hugging Face dataset of 1,245,391 synthetic decision-modelling examples carrying Jev teacher probability distributions, used for Claes training. Access is gated and requires manual approval of the repository conditions.
Jev Models & Reimplementations#open-models#calibration#evaluation
Community
arXiv paper describing a multi-agent trading system whose agents share only point-in-time stores and answer typed questions through Jev, testing whether LLM judgments of web news track the market's reaction to an event or follow a price move already reported.
Jev Demos & ExperimentsArticle#arxiv#agents#demo
Community
Open-weight eligibility scorer that LoRA-adapts Qwen models with a pointer head to score natural-language answer options in one forward pass, trained on TREC Clinical Trials 2021 and evaluated on 6,975 pairs from 50 unseen synthetic patients.
Jev Models & ReimplementationsArticle#arxiv#open-models#evaluation
Community
Multilingual benchmark of nine suites in 122 languages that evaluates typed decision models such as Jev, Clef, and pplx-decider, and tests whether confidence thresholds fitted on English transfer to other languages.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#benchmark
Community
Claude Code skill that reviews a finished video before publishing: Jev checks every frame against character reference sheets, Gemini watches with sound, GPT reviews still frames, and Claude returns a timestamped repair list.
Jev Agents & MCP#claude-code#agents#guardrails
Provider-neutral CLI, Claude Code plugin, and MCP server that asks yes/no, choice, score, or rank questions about text and returns probabilities. Talks to Jev, Jev via OpenRouter, the OpenAI Decisions API, or Claude.
Jev Agents & MCP#mcp#cli#claude-code
Community
0GitHub stars
A Claude Code skill with two Python scripts that walk an inbox mail by mail, sorting each message into ACT, WAIT, FYI or NOISE. Every mail text passes a Jev prompt-injection guard before the agent reads it, and no code in the repo can send mail.
Jev Agents & MCP#claude-code#guardrails#security
A LoRA adapter for Qwen3-Omni-30B-A3B-Instruct that scores a therapist's spoken response on the eight Facilitative Interpersonal Skills items, returning a 1-5 distribution and expected value per item from video, audio, and transcript in one forward pass.
Jev Models & Reimplementations#huggingface#calibration#evaluation
Community
A LoRA adapter for JEV-9B-MLX-NVFP4 that judges the shell commands an AI coding agent wants to run and decides whether each one can execute without asking the user. It is the local judge behind the omp command gate in Quentin-M/harness.
Jev Models & Reimplementations#open-models#security#guardrails
Community
arXiv paper evaluating Jev as a safety guardrail for a Qwen2.5-1.5B-based pipeline across 970 benchmark prompts, comparing an unfiltered LLM, Jev input filtering, and tiered input filtering with selective output review.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#guardrails
Community
Node.js library and CLI that compares two images through Jev, returning a 1–10 similarity score, located differences with bounding boxes, and per-difference fix suggestions. Handles PNG and JPEG, optional caching, and offline HTML reports.
Jev Tools & CLIs#typescript#cli#madewithjev
Community
0GitHub stars
A Node.js and pnpm sample project for the TypeSafe AI JavaScript SDK 0.7.0, made because that SDK version fails on Bun with a "Body already used" error. Ships runnable Noul, Choice, Score, and Box examples plus image queries.
Jev Repos & SDKs#github#typescript#sdk
A Hugging Face Space published by chaoliangUNSW under the slug jev-style-2b-v4-2, titled JevStyle v4.2 · Typed Decisions. It runs on Zero GPU hardware and presents the standard App, Files, and Community tabs for visitors.
Jev Models & ReimplementationsPlayground#open-models#playground#demo
Community
Hugging Face dataset of Jev decision-index results from the mjev-vl-4b vision-language checkpoint, pairing decision and probability outputs with execution metadata, image budgets, latency, and SHA-256 hashes for weights and inference code.
Jev Benchmarks & Evaluations#evaluation#calibration#benchmark
Community
arXiv study adapting an online shopping experiment to three decision models, including Jev, to test whether digital nudges steer non-generative System One models. Reports 600 runs per model and compares default and social-influence choices against a control.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#research
Community
Hugging Face dataset of teacher judgments for ROR affiliation point matching, named for Jev distillation. Each row pairs an affiliation text with ROR identifiers and calibrated probabilities, across 200k rows in train and validation splits.
Jev Benchmarks & Evaluations#calibration#evaluation#classification
Community
A sentence-transformers retriever for ROR set point matching, distilled from OpenAlex's Jev judgments. It returns candidate ROR records for an affiliation string and is fine-tuned from intfloat/multilingual-e5-base under an MIT license.
Jev Models & Reimplementations#open-models#python#research
Community
A cross-encoder set model for ROR set point matching, distilled from OpenAlex's Jev judgments. Given an affiliation string and its candidate ROR records, it gives each candidate the probability that the string names it.
Jev Models & Reimplementations#open-models#python#classification
Community
arXiv paper auditing three remedy-decision systems on US consumer financial complaints: GPT-4o-mini, GPT-5-mini, and Jev, a probabilistic System One model returning a distribution over remedies. It separates group-scale disparities from individual decision instability.
Jev Benchmarks & EvaluationsArticle#arxiv#evaluation#benchmark
Community

Start here with the Jev AI model

Hand-picked entries the maintainers recommend first, from official primitives to community tools.

The Jev Day release post: Jev 1.14.0 under jev-preview plus three danger-zone features — composable images on both models, the box question type on 1.14 only, and opt-in 262k context.
Jev Guides & ArticlesArticle#official#release#vision
Official
The box question type: one bounding box per question, returned as four edges that are fractions of the image, plus confidence, with no criteria field and no not-found value.
Jev Practices & PatternsDocs#official#docs#vision
Official
LiteLLM's Day 0 post for TypeSafe Jev 1.14: the proxy adds box questions, image input and long-context mode on both POST /v1/systemone and POST /v1/decisions, forwarding TypeSafe-Danger-Zone headers only to TypeSafe deployments.
Jev Integrations & AdaptersArticle#community#litellm#gateway
Community

From the Jev community

Watch walkthroughs, read the threads, and see what builders are posting.

YouTube: KodeKloud's three-minute primer: what a System One model decides, and why it answers in milliseconds.

YouTube: Caleb Writes Code explains what Jev is and how to call it, in seven minutes.

YouTube: Greg Isenberg and Ryan Vogel on the businesses Jev unlocks, and a path in through the Vercel AI Gateway.

YouTube: CJ from Syntax demos browser use, classification, code review, a model router, and a chat bot with no LLM.

YouTube: Ryan Vogel runs Jev on 100 and then 1,000 emails: category, priority, spam, and reply predictions.

YouTube: AICodeKing tests support routing, refund detection, prompt-injection resistance, and browser automation.

Hacker News: Show HN: Ad Spend Guard gates budget before the auction, not the creative after.

Show HN: Gating ad budget with a decision modelRead the thread on Hacker News

Reddit: Reranking rebooking options with a decision model, ranked with reasons.

Hacker News: Pick Verify: a single decision at the warehouse pick station catches confusable picks.

Show HN: Verifying robot picks with a decision modelRead the thread on Hacker News

Hacker News: Software Bombe and live Enigma demo where Jev ranks cribs and judges plaintext.

ag_212 pointsShow HN: Jev as the Bletchley Park Analyst: A Software Bombe on EnigmaRead the thread on Hacker News

Hacker News: Show HN for the decide CLI: brew install, file context, and multi-question shell scripts.

vsekhar2 pointsShow HN: Decide – Jev decisions in the shell, scripts, and agent skillsRead the thread on Hacker News

How entries are chosen

Every entry is reviewed against the same bar, whether it comes from TypeSafe or the community.

  • Public and working: no paywalls, sign-up walls, or dead links.
  • Concrete: it has to be about Jev and the System One API, not generic LLM content.
  • Useful today: something a developer can learn from or use right now.
  • Distinct: if a similar entry exists, the description has to say what makes this one different: a different runtime, a cheaper path, a measured result, or a narrower focus.
  • Documented: repos state their license, and docs are in English or carry an English summary.

Spam, affiliate links, and thin AI-generated content are rejected. New entries are expected to ship with a deep dive: two to five highlights, caveats, a quickstart snippet where one helps, and a verification date. Star counts are refreshed when an entry is touched.

Common questions

Short answers about Jev and how this directory works.

What is the Jev AI model?

Jev is TypeSafe AI's first System One model, an AI model that takes a state plus typed questions and returns one structured answer per question: a choice, an ordered score, or the probability of yes, with calibrated confidence on Choice and Score answers. Code can branch on the result without parsing generated text.

What is the difference between Choice, Score, and Noul?

They are the three question primitives. Choice picks one of up to 255 options, Score rates on 2 to 10 ordered levels, and Noul answers yes or no. Choice and Score answers carry a confidence between 0 and 1; a Noul answer is the probability of yes.

Which Jev SDKs and client libraries are available?

TypeSafe maintains official JavaScript/TypeScript and Python SDKs plus a Python adapter. The community has built clients for Go, .NET, PHP, Laravel, Rust, Elixir, Ruby, and Scala, along with framework integrations such as DSPy, LlamaIndex, and Home Assistant. All of them are listed in the Repos & SDKs category.

Is the directory free, and is it affiliated with TypeSafe AI?

The directory is free to browse: every entry is reviewed, and spam, affiliate links, and sign-up walls are rejected. JevDirectory.org is community-run and not affiliated with TypeSafe AI; Jev and System One are TypeSafe AI trademarks.

How often is the directory updated?

Entries are added as new resources appear and re-checked when they are touched. The directory currently holds 3991 entries from 296 source sites, last updated Nov 13, 2026.

What is a verified deep dive?

Most entries include a deep dive: two to five highlight bullets someone would only know from using the resource, a caveats note about limits and requirements, an optional quickstart snippet, and the date the link was last checked. 3991 of the 3991 entries carry one today.

For the canonical details, read the official TypeSafe docs and the API reference.