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-use
Claude Code, Codex, and pi plugin plus MCP server and npm library that hands steps needing no text output to Jev: one batched call answers typed questions about a state, and an opt-in PreToolUse gate can only deny or ask.
- Category
- Tools & Integrations
- Published by
- Community
- Author
- shitianfang
- Added
- 2026-09-22
Tagscommunityjavascriptclaude-codecodexmcpskillscompaction
Highlights
- jev_judge batches typed noul, choice, and score questions about one state into a single Jev call.
- jev_gate is an opt-in PreToolUse gate that can only deny or ask, never silently allow.
- A typed escalation contract (writing, open_ended, oversized, unsure, unreachable) returns other steps to the LLM.
- An unreachable backend escalates instead of allowing, so an unjudged command is never waved through.
- Publishes its own live benchmarks, including the runs where Jev did worse.
Quickstart
bash
npx -y jev-use install
export TYPESAFE_API_KEY=YOUR_API_KEY
npx -y jev-use doctorWatch out
MIT-licensed. Needs Node.js and one of TYPESAFE_API_KEY, OPENROUTER_API_KEY, or AI_GATEWAY_API_KEY (JEV_BACKEND=mock runs keyless); judged state goes to the configured provider.
More like this
354GitHub stars
A Codex skill (with a plugin option) that hands clicks, toggles, navigation, and scrolling to Jev over accessibility text while Codex types, interprets visuals, and verifies the outcome.
Tools & Integrations#community#javascript#skills
Communityjev-browser-use
326GitHub stars
Wrappers for Claude Code and OpenAI Codex that ask Jev to choose a model tier for each fresh user turn while preserving each CLI's native interface, tools, sessions, permissions, and authentication. Ships as the jev-claude and jev-codex commands.
Tools & Integrations#community#javascript#claude-code
Communityjev-router
201GitHub stars
A local-first MCP server that gives Claude Code, Codex, Cursor, and OpenCode structured quality scores from Jev across correctness, complexity, tests, security, and other dimensions while the agent writes code.
Tools & Integrations#community#typescript#mcp
Communityjev-review
From 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