Little-Planet-Labs/jev-playground
Organization repository on GitHub
A small Next.js app for experimenting with TypeSafe AI's Jev model (System One)
- Forks
- 1
- Last pushed
- Updated Sep 2026
Repo stats from the GitHub API, cached Oct 2026.Homepage
CommunityJev Demos & Experiments
Jev Playground — Little-Planet-Labs
A minimal Next.js workbench for Jev: paste a state, mix noul, choice and score questions, and see the typed answers, probability distributions and confidence returned from a single parallel request.
- Stars
- 1
- Language
- TypeScript
- Published by
- Community
- Author
- Little-Planet-Labs
- Last verified
- Oct 2026
About this project
A small Next.js app for experimenting with TypeSafe AI's Jev model (System One). Paste a state, build any mix of noul (yes/no probability), choice (pick from options), and score (rate against a rubric) questions, and see the typed answers, probability distributions, and confidence in one shot — all questions are evaluated in parallel in a single request. Get an API key from the TypeSafe console. Open hit Load sample for the docs' support-ticket example, then Run (or ⌘↵).
Quoted from the project's README. Read the full README.
Works forJev for Classification
Used inJev for Software & DevTools
- Languages
- TypeScript
Highlights
- Builds any mix of the three primitives — noul for yes/no probability, choice over options, score against a rubric — and sends them in one request.
- Shows the typed answer, the full probability distribution and confidence per question, so a near-0.5 noul stays visible instead of flattening to a boolean.
- A Load sample button fills the docs' support-ticket example, which is the fastest way to see a real request before writing your own.
- Plain text state is sent as a string and valid JSON as structured state, matching the two forms the State docs describe.
Watch out
This is a scratchpad, not something to build on. The README describes one page, three question types and a Run button, with no CLI, no exported module, no saved histories and no test suite, so there is nothing here to depend on and nothing keeping the UI honest as the API moves. Because every question goes out in a single request, you cannot tell from the response which question cost what — the whole state is paid for once per run, and nothing in the README addresses batching, retries or caching. Plain text is sent as a string and valid JSON as structured state, so the state you are testing is whichever of those you pasted, and nothing in the README describes schema validation on it. Setup is a TypeSafe console key in .env.local, then npm install and npm run dev on port 3000. Copy reviewed against the repository README on 2026-10-04, not from running it.
Questions about this entry
Short answers drawn from the linked project or page.
Treat it as a local stand-in rather than an upgrade. The README points at the TypeSafe console for the key and loads the docs' own support-ticket example, which suggests it is modelled on that flow. What it does add is that all three question types go out together in one request, and the probability distribution and confidence come back next to each typed answer.
Both. The README says you see typed answers, probability distributions and confidence in one shot, so a noul sitting near 0.5 shows up as a distribution rather than a hard yes or no. That is the main reason to run your own state through it instead of reading about the behaviour.
The whole state is sent on every run, and all questions travel in the one request, so there is no way to attribute token cost to an individual question. The app keeps no history, which means each Run re-pays for the same state, and the README documents no caching or batching behaviour.
Only in the sense of how it chooses to send it: plain text goes as a string and valid JSON goes as structured state, with the README deferring to the State docs for what that means. No schema validation is described, so a malformed object is sent as it is and the response is where you find out.
Get an API key from the TypeSafe console settings page, put TYPESAFE_API_KEY=ts-... in .env.local, then run npm install and npm run dev and open http://localhost:3000.
The docs' support-ticket example; run it with the Run button or the Command-Enter shortcut, and the README screenshot shows the typed answers and probability distributions it returns.
Both. Plain text state is sent as a string, while valid JSON is sent as structured state, matching the TypeSafe state documentation, and all questions run in parallel in a single request.
Other listings of this project
Forks and copies of this project in the directory. This entry is the canonical one.
0GitHub stars
Zero-dependency local playground showing six Jev workflows from triage to eval judging with shippable snippets.
Jev Demos & Experiments#community#github
Community
AviroopPaul/jev-playgroundJavaScript
AviroopPaul/jev-playgroundJavaScript2GitHub stars
A Next.js playground that benchmarks Jev against GPT-5.6 Luna, Claude Haiku 4.5, Gemini 3.5 Flash Lite, and GPT-6 Astra in tic-tac-toe and Connect Four, giving every model the same legal-move Choice options through the Vercel AI Gateway.
Jev Practices & Patterns#community#typescript#evaluation
Community
hegargarcia/jev-playgroundTypeScript
hegargarcia/jev-playgroundTypeScript0GitHub stars
A MoonBit playground for TypeSafe's Jev: a client for GET /v1/models and POST /v1/systemone with noul, choice, and score questions, a single-query CLI, a Jev-vs-Jev gomoku game, and a tool that replays game logs as real-time GIFs.
Jev Repos & SDKs#community#moonbit#cli
Community
mizchi/jev-gomokuMoonBit
mizchi/jev-gomokuMoonBitAn independent browser playground that runs TypeSafe Jev on one question or several, with ready examples for routing, refunds, urgency, and the next agent action.
Jev Demos & ExperimentsPlayground#community#playground#tutorial
Community
2GitHub stars
A Vite app where Jev picks only closed-enum labels for a composition plan and code expands those into notes, engraving, audio and MIDI, with an offline heuristic stub when no key is set.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
wustep/jev-playgroundTypeScript
wustep/jev-playgroundTypeScriptMore Jev resources like this
98GitHub stars
Self-hosted Docker service and web UI that packages Laya structured-decision inference behind a compatible System One endpoint.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
1Panel-dev/laya-serverPython
1Panel-dev/laya-serverPython23GitHub stars
Browser drone-fleet lab where TypeSafe Jev steers each drone as fast reflexes and an optional planner offers one-use strategy advice when confidence drops, without pausing control.
Jev Demos & Experiments#community#jevbest#catalog-import
23GitHub stars
Chrome extension that sends each X post to Jev with six typed questions in one call near the viewport, then renders a behavior chip under the post plus a session cost and latency panel.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
oso95/x-scannerTypeScript
oso95/x-scannerTypeScript14GitHub stars
Manifest V3 Chrome extension in TypeScript that sends each LinkedIn post to Jev and collapses bait, self-promo, off-topic, and sponsored posts into a one-line bar with reasons and scores.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
stefw/lkcleanTypeScript
stefw/lkcleanTypeScript7GitHub stars
Demo that turns free-text UI descriptions into real shadcn components using only Jev typed Choice, Noul, and Score answers, with no generated code on the decision path.
Jev Demos & Experiments#community#jevbest#catalog-import
8GitHub stars
Claude-driven browser automation where plain-English chat drives Brave or Chrome, Jev makes on-page decisions, and a guard freezes irreversible clicks.
Jev Demos & Experiments#community#jevbest#catalog-import
Community
ranjan2829/AskJevTypeScript
ranjan2829/AskJevTypeScriptFrom the Jev guides
Original write-ups on what this entry is for.
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.
Jev Demos & Experiments#gaming#agents#control
Read article
From the Jev community
Posts from builders shipping with Jev right now.