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The full directory

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.

Entries
3,739
Categories
11
Official
102
Community
3,637
Source sites
292
Deep dives
3,739

By format

3739
  • Docs169
  • Repos & sites2980
  • Videos73
  • Posts103
  • Articles344
  • Playgrounds70

Updated

Browse the Jev AI model by category

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

Browse the Jev AI model by use case or industry

The same directory, sliced by what you are building and who you are building it for.

Jev use cases13 ways to put Jev to work, from classification and routing to decision gating and evaluation.
Jev industries14 sectors building with Jev, from software and security to healthcare and robotics.

All 3739 Jev AI model resources

Search the full directory, or filter by category and tag.

Showing 1–48 of 54 resources

LangChain
148kGitHub stars
LangChain is the agent engineering platform: an MIT-licensed Python framework from the LangChain team for building agents and LLM applications by chaining interoperable components with third-party model, tool, and vector-store integrations.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitylangchain-ai/langchainPython
Composio
30.6kGitHub stars
Composio is an MIT-licensed SDK monorepo giving AI agents 1,000+ pre-authenticated toolkits with per-user sessions, authentication, triggers, and a sandbox, and it ships TypeScript and Python adapters including one for TypeSafe (Jev).
Jev Repos & SDKs#community#catalog-import#cobanov
Communitycomposiohq/composioTypeScript
LangChain.js
18.3kGitHub stars
LangChain.js is the TypeScript edition of LangChain, a framework for LLM-powered applications that runs on Node.js, Cloudflare Workers, Vercel and Next.js, Supabase Edge Functions, browsers, Deno, and Bun.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitylangchain-ai/langchainjsTypeScript
Effect
17.3kGitHub stars
Effect is a TypeScript library for production-grade applications, covering typed errors, dependency injection, structured concurrency, scheduling, tracing, and schema validation; 4.x is a long-term support release.
Jev Repos & SDKs#community#catalog-import#cobanov
Communityeffect-ts/effectTypeScript
BAML
9.4kGitHub stars
BAML is Boundary's Apache-2.0 programming language for agents: TypeScript-looking syntax, a Rust-like type system that persists at runtime, typed errors, green threads, and callable from TypeScript, Python, Go, C#, and Java.
Jev Repos & SDKs#community#catalog-import#cobanov
Communityboundaryml/bamlRust
Nautilus Compass
1.3kGitHub stars
Nautilus Compass is a local-first memory and reliability layer for AI agents: SOTA retrieval on LongMemEval-S, drift detection before agents act, cross-agent contracts, plus MCP, caliber-bench, and NACRE judging artifacts.
Jev Agents & MCP#community#catalog-import#cobanov
Communitychunxiaoxx/nautilus-compassPython
JevPilot
224GitHub stars
A playable Three.js driving simulator where Jev-powered autopilot picks steering and speed up to four times per second: compact tables of eligible paths, traffic and road boundaries go to Jev while geometry and control math stay local.
Jev Demos & Experiments#community#catalog-import#cobanov
Communitystandardagents/jevpilotJavaScript
Phocinae-Largha-150M-v1
167GitHub stars
A 144.3M-parameter bilingual typed decision model fine-tuned from jhu-clsp/mmBERT-small: it answers noul, choice, and score questions in one forward pass with calibrated confidence and zero output tokens, and it runs on CPU.
Jev Models & Reimplementations#community#catalog-import#cobanov
Communityphocinae/phocinae-largha-150m-v1Python
VideoJev
162GitHub stars
A System One model family for video: VideoJev-4B and VideoJev-35B-A3B perform temporal grounding and multiple-choice video QA by scoring candidates directly, returning probabilities instead of generated text.
Jev Models & Reimplementations#community#catalog-import#cobanov
Communitymcg-nju/videojevPython
Laya Vision
91GitHub stars
An independent fork of Laya that replaces its text encoder with a small vision-language model, giving calibrated typed decisions over an image plus text in one forward pass from a 201M-parameter SmolVLM-256M backbone.
Jev Models & Reimplementations#community#catalog-import#cobanov
Communityr33drichards/laya-visionPython
Parallel Constrained Decoding
15GitHub stars
A Java and Python implementation of parallel constrained decoding: fill a whole JSON schema of booleans and enums in two forward passes, with calibrated confidence per field and output that is schema-valid by construction.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitystephanj/parallelconstraintdecodingJava
Médula
12GitHub stars
A reproducible lab measuring how several coding agents coordinate on one repository, plus Médula, a kernel that asks TypeSafe Jev before every write whether a change collides with what the other agents are doing.
Jev Benchmarks & Evaluations#community#catalog-import#cobanov
Communityjoaquinruiz/medulaPython
OpenJevSwift
10GitHub stars
A native Swift implementation of OpenJev, the Jev-compatible typed-decision server: send a state and typed questions over a Jev-compatible HTTP API and read every answer from model probabilities, on Apple silicon Macs or inside iPhone and Mac apps.
Jev Repos & SDKs#community#catalog-import#cobanov
Communityalgorythm-canada/openjevswiftSwift
open-bonsai-jev
8GitHub stars
An independent reimplementation of the OpenJev mechanism on PrismML's 1.75-bit Bonsai weights: typed decisions read straight off the next-token distribution of a 5.95 GB 27B model in one forward pass.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitynicolailassen/open-bonsai-jevPython
Awesome Open System One
9GitHub stars
A curated list tracking the open side of the System One ecosystem — runnable Jev-like models, independent benchmarks, and calibration and constrained-decoding tooling — as the counterpoint to lists about the closed hosted Jev.
Jev Guides & Articles#community#catalog-import#cobanov
Communityrupeshpoojary9/awesome-open-system-one
opencode-jev-orchestrator
7GitHub stars
An OpenCode plugin that keeps the session on a cheap sticky parent model so the cache stays warm, and asks Jev whether a turn is hard before escalating through jev_escalate to temporary stronger subagents.
Jev Integrations & Adapters#community#catalog-import#cobanov
Communityaaronshaf/opencode-jev-orchestratorTypeScript
JEV Tetris
6GitHub stars
A playable Tetris where Jev never sees the board: code enumerates every legal placement as a sentence and Jev returns a probability for each in about 380 ms. The field glows with the whole distribution before the piece drops.
Jev Demos & Experiments#community#catalog-import#cobanov
Communitythelau/jev-tetrisJavaScript
jevr
5GitHub stars
A native R client for Jev and TypeSafe System One: send a state plus typed questions and get structured answers back in R. Supports jev_choice, jev_score and jev_noul questions, several questions per evaluation, and jev_map over many states.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitysimxnherrera/jevrR
sokudan (即断)
4GitHub stars
A Japanese System One decision model built on modernbert-ja-310m: send text and typed questions and get typed answers with probabilities from one forward pass, no text generation, at 314.6M parameters that also run on a CPU.
Jev Models & Reimplementations#community#catalog-import#cobanov
Communityhiroki-abe-58/sokudanPython
classifier-benchmark
3GitHub stars
Head-to-head benchmark for System One-style classification models across choice, noul and score questions. Jev led both hash-locked suites at 0.974 micro accuracy on v1 (8 tasks, 78 cases) and 0.964 on v2 (49 tasks, 866 cases), ahead of local Von 1.1, GLiNER2 and Laya.
Jev Benchmarks & Evaluations#community#catalog-import#cobanov
Communityjabr/classifier-benchmarkPython
jev-scout
3GitHub stars
An MCP stdio server that judges every research step: guarded_search, guarded_fetch and research_report score each query, result and fetched page with Jev for relevance, credibility and steering risk, with budgets, SSRF-guarded fetching and a live SSE dashboard.
Jev Agents & MCP#community#catalog-import#cobanov
Communitykierandotai/jev-scoutTypeScript
Prosodia — an audio Jev
2GitHub stars
An audio-native decision model shaped like Jev: audio is encoded once, several typed questions branch over that single encoding, and answers come back as calibrated probability distributions — no transcript, no ASR, the Whisper decoder never runs.
Jev Repos & SDKs#community#catalog-import#cobanov
Communityalperiox/audio-jevlikePython
JevGuard MCP Server
2GitHub stars
Official MCP server for JevGuard and TypeSafe AI: zero-dependency guardrails over JSON-RPC 2.0 on stdio, gating shell commands and code patches, caching decisions in local SQLite and pruning state.
Jev Agents & MCP#community#catalog-import#cobanov
Communityseb4ez/jevguard-mcpPython
jev-eval
1GitHub stars
Benchmark harness that scores TypeSafe Jev against any OpenRouter model or local checkpoint on labelled classification data: accuracy, calibration (ECE), confidence distribution, latency and cost across five tasks with 300 items each.
Jev Benchmarks & Evaluations#community#catalog-import#cobanov
Community4esv/jev-evalPython
Decima
1GitHub stars
Open, CPU-sized Jev-style decision model: give it a situation, a question and options, and Decima returns calibrated probabilities in roughly 20-50 ms per decision as int8 ONNX, with no GPU, no API key and nothing leaving the machine.
Jev Models & Reimplementations#community#catalog-import#cobanov
Communityamyrmahdy/decimaPython
JEV Decision Benchmarks
1GitHub stars
Benchmark results for JEV 1.13 in Choice mode across MetaTool, When2Call and BFCL V4: tool selection, abstention and hallucination tables with bilingual reports and CSV data.
Jev Benchmarks & Evaluations#community#catalog-import#cobanov
Communitybaibizhe/jev-decision-benchmarksPython
Jev for Google Sheets
1GitHub stars
A Google Sheets add-on that classifies, tags and scores text with plain-language formulas: JEV_IF, JEV_PROB, JEV_CHOICE and JEV_SCORE return typed values, and uncertain rows can say UNSURE instead of guessing.
Jev Integrations & Adapters#community#catalog-import#cobanov
Communitycab14bacc/jev-sheetsTypeScript
Hunch
1GitHub stars
Probabilistic control flow for TypeScript: Hunch asks a System One model such as Jev yes/no questions, thresholded booleans, picks and ratings, and returns typed answers you can branch on in ordinary code.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitycarldaws/hunch-tsTypeScript
jev-measured
1GitHub stars
Measured cost, latency, accuracy and raw output from the live Jev API across twelve realistic use cases, plus twelve other decision models on the same 633 items. Reproducible with your own key; the whole measured Jev run cost under one cent.
Jev Benchmarks & Evaluations#community#catalog-import#cobanov
Communitywallerchen/jev-measuredPython
AlgoVault Integrations
0GitHub stars
Examples for consuming the AlgoVault Verifiable-Signal v1.0 spec across trading and execution platforms — FreqTrade, Hummingbot, 3Commas, Coinbase AgentKit and others — plus a decision-layer example whose transformer returns a TypeSafe SystemOneRequest that Jev answers before code applies every threshold.
Jev Integrations & Adapters#community#catalog-import#cobanov
Communityalgovaultlabs/algovault-integrationsTypeScript
jev-palette
0GitHub stars
A semantic command palette demo where Jev ranks 77 commands by intent in Portuguese or English: one Choice question per keystroke, with the full probability distribution over the command catalog as the ranking. Runs side by side with a classic fuzzy matcher that fails honestly on the same queries.
Jev Demos & Experiments#community#catalog-import#cobanov
Communityamycardoso/jev-paletteJavaScript
Chess with Jev
0GitHub stars
Browser chess and Chess960 where code works out every legal move's facts and Jev picks one per turn as a single typed Choice; the mirror of the chriswijnia.com/lab/chess monorepo.
Jev Demos & Experiments#community#catalog-import#cobanov
Communitycwdx/chess-with-jevTypeScript
Jevvie (browser companion)
0GitHub stars
A website companion's code: a page's actions are offered as WebMCP tools, a visitor's request becomes one Jev Choice, and a three.js voxel character hops to the button and does it.
Jev Demos & Experiments#community#catalog-import#cobanov
Communitycwdx/jevvieTypeScript
Jev SEO Audit
0GitHub stars
Audits any business site for SEO and AI-search visibility: a deterministic crawl feeds narrow typed Jev judgements that stream into a live dashboard page by page, with no LLM-authored findings.
Jev Tools & CLIs#community#catalog-import#cobanov
Communitydeploymates/jev-seoTypeScript
TypeSafe Java Client
0GitHub stars
A Java 21 client and CLI for the TypeSafe API: send state with Noul, Choice, and Score questions, get typed answers, and optionally run local Clef and Laya models via ONNX Runtime with no API key.
Jev Repos & SDKs#community#catalog-import#cobanov
Communitydfa1/typesafe-javaJava
Strayguard
0GitHub stars
A git pre-commit hook that asks TypeSafe Jev whether each new file belongs in your repo, catching scratch scripts, debug dumps, build output and local config before they land. Local rules run first, so .env and .DS_Store are matched locally and never sent anywhere.
Jev Tools & CLIs#community#catalog-import#cobanov
Communityeve2512/strayguardPython
jev-rag-guard
1GitHub stars
A typed-decision accuracy layer for RAG pipelines that wraps the seam between retrieval and generation with six cheap checks: intent, relevance, clarify, sufficiency, grounding and caveat. Each check returns a calibrated probability you can threshold and log.
Jev Repos & SDKs#community#catalog-import#cobanov
Communityfurkandrms/jev-rag-guardPython
pi-jev-compact
0GitHub stars
A Pi extension for selective, verbatim context compaction: Jev scores every tool call and its result, unneeded calls are dropped, and everything kept stays byte-identical. The README measured 15.5% reclaimed on a synthetic window, rising to 33.5% with prose included.
Jev Integrations & Adapters#community#catalog-import#cobanov
Communityilkerulusoy/pi-jev-compactTypeScript
judge_rails
0GitHub stars
A Ruby gem that turns typed Jev judgments into ordinary ActiveRecord attributes: Noul, Choice and Score answers become indexable, sortable columns with SQL scopes like urgency_above(0.8). It also works as a plain Ruby client with no Rails.
Jev Integrations & Adapters#community#catalog-import#cobanov
Communityjust-the-v/judge_railsRuby
Jev Unpack hook
0GitHub stars
A Codex and Claude Code Stop hook that detects overloaded multi-topic messages and forces the agent to present issues one at a time with context and missing info, using two Jev Choice questions behind confidence thresholds.
Jev Integrations & Adapters#community#catalog-import#cobanov
Communitylucaminudel/jev-unpack-hookPython
jev-decoder
0GitHub stars
A set of experiments that uses TypeSafe's Jev as a decoder through its Choice primitive, sampling ASCII characters, BPE tokens and grammar-constrained SQL from Jev's probability distributions, and measuring next-character loss against uniform sampling on tiny-shakespeare.
Jev Demos & Experiments#community#catalog-import#cobanov
Communitypanalexeu/jev-decoderPython
Chess — Chris Wijnia
An interactive chess experiment on chriswijnia.com: play Jev, TypeSafe's System One model, a simple engine or a friend, or watch Jev play itself. Each turn Jev weighs every legal move at once as one typed Choice and shows how sure it is.
Jev Demos & ExperimentsPlayground#community#catalog-import#cobanov
Community
1 Million Emojis — Chris Wijnia
A shared 1,000 by 1,000 emoji canvas where visitors paint and Jev paints alongside them: after each stroke it reads what is around it by name, weighs emoji that belong with it, and paints one or finishes a shape it is sure you meant.
Jev Demos & ExperimentsPlayground#community#catalog-import#cobanov
Community
Jevvie — Chris Wijnia
Jevvie is the companion in the corner of every page on chriswijnia.com: ask it for something and Jev picks which of the page's actions you mean, one typed Choice at a time, then Jevvie hops over and does it. The same actions are WebMCP tools.
Jev Demos & ExperimentsPlayground#community#catalog-import#cobanov
Community
When a Judgment Layer's Self-Reported Fields Lie
Perry Link's Zenodo preprint compares three judgment layers - a local Laya judge, TypeSafe Jev and DeepSeek-V4.1-Flash - on the same 120-checkpoint task, reporting that cost is not the binding constraint, that p50 latency spans about 25-32x, and that the judges' self-reported fields fail in clustered ways.
Jev Benchmarks & EvaluationsArticle#community#catalog-import#cobanov
Community
Decima Playground
A Hugging Face Space for the Decima decision model: choose a preset or write your own question, list possible answers, and paste any text you want the model to consider. The app then shows the probability for each answer.
Jev Demos & ExperimentsPlayground#community#catalog-import#cobanov
Community
Ultra-small System One Models in Your Browser
A Hugging Face Space that runs a tiny System One model entirely in the browser: type a prompt and the app produces output on the spot, with no server connection or installation required.
Jev Demos & ExperimentsPlayground#community#catalog-import#cobanov
Community
Jevfast
A community gallery of Jev use cases and experiments drawn from projects, X posts, and videos, reporting 319 projects, 273 X posts, and 261 videos at review time, with language filters and a submit-content form.
Jev Guides & ArticlesArticle#community#catalog-import#cobanov
Community

Start here with the Jev AI model

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

Jev: For the Builders AND Dreamers (Jev 1.14)
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
Box Questions (Dreamer-Ready)
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
Jev 1.14 Day 0 Support in LiteLLM
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

Newest Jev AI model resources

The latest additions to the directory, newest first.

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: Decision Index 0.2.1 scores open reproductions of Jev on a frozen suite.

jackbravo4 pointsDecision Index 0.2.1 – 70 open reproductions of TypeSafe Jev's 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

Follow @typesafeai

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 3739 entries from 292 source sites, last updated Oct 25, 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. 3739 of the 3739 entries carry one today.

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