jevplayground
Browser-only Jev testbed via Vercel AI Gateway for building boolean, choice and score questions and viewing probabilities and cost.
Overview
Jev Playground is a single static page for trying Jev through the Vercel AI Gateway. You paste a gateway API key, pick a work or fun preset or write plain-text or JSON state, build boolean, choice or score questions, and press Evaluate. It shows verdicts, probability bars, latency, token usage and estimated cost, and lets you set an auto-accept threshold to see which answers would need human review.
There is no backend: the page calls the gateway's evaluation-model endpoint directly from the browser, and the key is held in memory unless you choose to remember it in localStorage. Results can be shared as an image or link that reopens the setup without the key. The README documents the exact HTTP call the AI SDK makes, including a header omitted because of CORS. It is useful for developers learning Jev's question types or prototyping a decision before coding.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Yes / no | User-defined boolean question with optional true/false criteria | — |
| Choice | User-defined choice over named options | — |
| Score | User-defined score over ordered levels | — |
How it works
- Paste an AI Gateway key and choose a preset or write state
- Build boolean, choice or score questions
- Evaluate; the browser calls the gateway directly
- Inspect probabilities, cost and which answers fall below the auto-accept threshold
- Copy an AI SDK or curl snippet, or share the setup
Strengths
- No backend; key only goes to the gateway
- Shows latency, tokens and estimated cost
- Threshold view previews human-review volume
- Generates code snippets
Caveats
- Requires a Vercel AI Gateway key
- Remembered keys are stored in localStorage
- Playground only, not a library
Getting started
npx serve public (or python3 -m http.server -d public 5173), or use the live site.At a glance
- Type
- Service
- Status
- prototype
- Language
- JavaScript
- Runtime
- static browser page
- Has code
- yes
Use cases and integrations
How curated lists describe it
Browser-only playground for Jev (TypeSafe AI's decision model) via Vercel AI Gateway.
hellogumbo/awesome-jev
Frequently asked questions
Where does my key go?
Only to the Vercel AI Gateway endpoint, from your browser; it is not included in shared links or images.
What does the auto-accept threshold do?
It shows which answers would pass automatically and which would need human review.
Do I need a TypeSafe key?
No, it uses a Vercel AI Gateway key to reach Jev.
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