Why open this playground instead of calling the Jev API directly?

Direct calls are fine for production. This adds preset scenarios, an editable state plus questions pane, and typed answers with probabilities side by side, so you can iterate on wording before wiring the API into code.

Which provider should I pick for a first experiment?

Any of the three. OpenRouter, Vercel AI Gateway, and the TypeSafe API are selectable in the top bar with their own model IDs, and the key is forwarded per request in x-provider and x-api-key headers.

Does the playground server store the key I paste?

No. The key stays in browser localStorage and travels one way to the selected provider through this server. The server never stores or logs it, and the digest documents that flow explicitly.

Can I host it for teammates without handing out keys?

Yes. Set OPENROUTER_API_KEY, AI_GATEWAY_API_KEY, or TYPESAFE_API_KEY as server-side fallbacks as shown in .env.example, so visitors never have to paste keys. The top bar theme switch also supports ?theme=swiss.

How do I run the playground on my own machine?

Run npm install then npm run dev, open http://localhost:5173, pick a provider in the top bar and paste your key via the Key button. The key stays in the browser's localStorage and is forwarded per request in x-provider and x-api-key headers.

What are the three question types and what does each return?

noul asks whether a statement is true and returns a probability from 0 to 1, with optional criteria given as both or neither. choice picks one of your criteria keys and returns choice plus probabilities and confidence. score rates on ordered criteria levels and returns an interpolated score plus probabilities and confidence.

Can I change how the playground looks?

The top bar switches between the BlockFrame (candy) and Swiss themes, and you can also open the app with ?theme=swiss in the URL.

CommunityJev Demos & Experiments

Tryjev

Browser playground for trying Jev decisions: pick a preset scenario, edit state and typed noul, choice, or score questions, then read probabilities back. Runs against OpenRouter, Vercel AI Gateway, or the TypeSafe API with your own key.

See highlights

Open github.com

Stars: 7
Language: Svelte
License: MIT
Published by: Community
Author: sugarforever
Last verified: Oct 2026

sugarforever/tryjev

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Jev Playground

Forks: 5
Last pushed: Updated Sep 2026

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About this project

A playground for Jev, TypeSafe AI's fast decision model: preset scenarios on the left, an editable state plus typed questions in the middle, typed answers with probabilities on the right. Bring your own key and pick a provider: OpenRouter (typesafe/jev-1.13, alpha.decisions), Vercel AI Gateway (typesafe-ai/jev, AI SDK experimentalevaluate) or TypeSafe's own API (jev-latest, POST /v1/systemone).

Quoted from the project's README. Read the full README.

Tagscommunity jevbest catalog-import svelte

Works forJev for Classification Jev for Routing Jev for Ranking

Used inJev for Software & DevTools

Highlights

Preset scenarios on the left, editable state plus questions in the middle, answers with probabilities on the right.
Works with OpenRouter, Vercel AI Gateway, or the TypeSafe API with selectable model IDs.
Keys stay in browser localStorage and travel per request; the server never stores or logs them.
Local run is npm install plus npm run dev, with server-side key fallbacks for private deploys.

Watch out

Bring your own provider key; private shared deployments need a server-side fallback key. 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.

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