Jev by @typesafeai is now on OpenRouter, in beta. Jev is a System One model. Instead of generating text, it takes your app's state plus a typed question and returns a typed decision with a probability attached. There is no JSON prompting, parsing layer, and nothing to validate Show more
Jev by use case
Decision gating
10 curated entries. Act on an answer only when confidence clears a threshold, otherwise confirm or escalate.
By format
- Repos & sites10
10 resources
1.1kGitHub stars
A local yes/no decision model that speaks Jev's wire format on a laptop CPU, refusing Choice and Score until those question types ship.
Models & Reimplementations#community#python#open-models
Community
feder-cr/jevPython
feder-cr/jevPython7GitHub stars
A Python server in front of llama-server that reads one-token label probabilities and exposes them as POST /v1/systemone.
Models & Reimplementations#community#python#open-models
Community
khimaros/verdictPython
khimaros/verdictPython344GitHub stars
A multimodal decision model that scores text, image, and video candidates with a shared head on Qwen3.5, plus SFT and experimental RLCD training code.
Models & Reimplementations#community#python#open-models
Community
Liuziyu77/ValenPython
Liuziyu77/ValenPython323GitHub stars
A single-binary MCP tool named evaluate that sends Noul, Choice, and Score questions to hosted Jev or a local System One server.
Agents & MCP#community#go#mcp
Community
itsmostafa/system-one-connectorGo
itsmostafa/system-one-connectorGo18GitHub stars
Claude Code hooks that narrow a roster in YAML, ask Jev which handler owns a prompt, and log the band before anything is blocked.
Agents & MCP#community#python#coding-agent
Community
AgriciDaniel/gatekeeperPython
AgriciDaniel/gatekeeperPython37GitHub stars
A Java gateway that asks Jev four questions about a deposit or withdrawal, then applies a direction-aware routing matrix in code.
Tools & CLIs#community#java#security
Community
klauswg/jev-guardJava
klauswg/jev-guardJava33GitHub stars
Four Java checkers — sponsored video, hiring fit, edit fidelity, and rental listings — that keep thresholds and vetoes in unit-tested code.
Tools & CLIs#community#java#verification
Communityklauswg/jev-suiteJava
klauswg/jev-suiteJava33GitHub stars
A Clash Royale bot that turns a phone screenshot into JSON once a second and asks Jev for a strategy, a card, and a square.
Demos & Experiments#community#python#gaming
Community
bytelabs-oss/clash-jevPython
bytelabs-oss/clash-jevPython562GitHub stars
A Mineflayer agent for Minecraft Java 1.16.5 where a planner sets the objective and Jev picks the next bounded action from game observations.
Demos & Experiments#community#javascript#gaming
Community
rmalde/minecraft-agentJavaScript
rmalde/minecraft-agentJavaScript21GitHub stars
An MCP proxy and hooks adapter that screens an agent's tool calls before they run and the tool results before the agent reads them, with thresholds in a policy file.
Agents & MCP#community#mcp#security
Articles
Original guides that go deeper on decision gating.
A base URL is the whole client change. What still works when Ollaya, Lichen, verdict, Rizzo Flow, or jevos answers POST /v1/systemone on your machine.
Models & Reimplementations#open-models#local#api
Read article
Jev labels a record that already exists. Code moves, flags, or holds it. How the document, mail, and transfer tools keep the action out of the model.
Tools & CLIs#classification#email#security
Read article
A game tick is a state plus a legal action list. How Clash Royale, Minecraft, and the earlier Mario, Pokémon, StarCraft, and drone loops ask Jev one step at a time.
Demos & Experiments#gaming#agents#control
Read article
Watch: Jev in action
Video walkthroughs and demos from the community.
YouTube: Gary Explains the catch: Jev understands natural language but answers with structured values and confidence.
YouTube: Sam Witteveen on System 1 thinking, then Choice, Score, and Noul demos, and chained actions.
YouTube: Nate Herk compares speed and cost against ordinary models, then builds an X feed classifier and a paper-trading prototype.
Discussions
Threads from Reddit and Hacker News about building with Jev.
Hacker News: Vercel on using Jev for defined decisions and GPT-6 Astra when the job also has to write or use tools.
flashbrew4 pointsTypeSafe AI Jev vs. GPT-6 AstraRead the thread on Hacker NewsReddit: A skeptical read of the calibration claim: no ECE or reliability curves published.
Hacker News: Kev: a tiny Jev-like family built on Qwen3.5
tosh458 points · 199 commentsKev: Tiny Jev-like family of decision models built on top of Qwen3.5Read the thread on Hacker NewsHacker News: Jev-Leftpad: the joke that measures how cheap decisions are
fka233 points · 87 commentsJev-LeftpadRead the thread on Hacker NewsFrom the community
Posts from builders shipping with Jev right now.
Jev lands on OpenRouter
700 leads scored for $0.09
JEV is INSANE. We gave it 700 high-intent leads and personalised outreach messages. In 40 seconds, it predicted how each message would perform, assigned a confidence score and detected lead-message mismatches. All for just $0.09. JEV can also score leads, analyse buying Show more
Beating Gemini Flash Lite on an eval
Ran @typesafeai's Jev against an existing classifier eval that previously used Gemini 2.5 Flash Lite. It won both on quality (saturated the eval) and speed (6x)
Browser Use Ultrafast, powered by Jev
Breaking: Browser Use + Jev = Ultrafast ⚡ Findings flights took 7s and cost only $0.0039 🤯 > new action space every step > DOM state space > small LLM fallback to type (this video is at 1x speed btw) Built a tiny open source browser agent. try it below ↓
A really smart switch statement
hype-free explanation of jev: jev does not replace gpt / claude jev is just a *really* smart switch statement like if 2016 ml classifiers got 2026 levels of intelligence it's a new* type of tool that will make a lot of workloads insanely fast, cheap, and accurate * = and by Show more
@CompleteSkeptic
After co-inventing ChatGPT, I kept asking myself: why have superhuman chat models not led to AGI? I’ve spent the last 2 years in stealth building a new way to train models (RLCD), and a new type of frontier AI model that we are releasing today: Jev • 20-200x faster • 40-400x
When a designer gets Jev
when a designer gets access to Jev