jev-playground (Little-Planet-Labs)
Small Next.js app to paste a state, build noul, choice and score questions, and inspect Jev's typed answers and distributions.
Overview
Jev Playground by Little-Planet-Labs is a small Next.js app for experimenting with TypeSafe's Jev. You 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 for all of them in one request, since questions are evaluated in parallel.
Plain text is sent as a string state and valid JSON as structured state. A sample from TypeSafe's docs (a support ticket) can be loaded with one click. It is a developer tool for learning the API and prototyping questions rather than an application.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Yes / no | Any user-defined yes/no question about the state | yes · no |
| Choice | Any user-defined choice question | — |
| Score | Any user-defined rubric score | — |
How it works
- Add TYPESAFE_API_KEY to .env.local and run the dev server
- Paste a state or load the sample
- Build noul, choice and score questions
- Run and inspect answers and distributions
Strengths
- Quick way to prototype questions
- Shows full distributions and confidence
- Handles text and JSON state
Caveats
- Requires a TypeSafe key
- Local developer tool only
Getting started
Put TYPESAFE_API_KEY in .env.local, then npm install && npm run dev and open http://localhost:3000At a glance
- Type
- App
- Status
- prototype
- Language
- TypeScript
- Runtime
- Next.js app
- Has code
- yes
Use cases and integrations
How curated lists describe it
A web playground for entering state and decision questions, then inspecting Jev answers and probability distributions.
logicrw/awesome-jev-projectsA small Next.js app for experimenting with TypeSafe AI's Jev model (System One).
hellogumbo/awesome-jev
Frequently asked questions
What can I do with it?
Build and run any mix of Jev questions against a state and inspect the answers.
Does it accept JSON state?
Yes. Valid JSON is sent as structured state.
Do I need a key?
Yes, a TypeSafe API key in .env.local.
Related projects
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ProjectbetaJavaScriptSample Cloudflare Worker app with three playful demos, one per Jev primitive: Noul (is it a sandwich?), Score and Choice routing.
AppprototypeTypeScriptMinimal web playground to write freeform state, build custom Choice, Score and Noul questions and see live Jev probability distributions.
AppprototypeTypeScript- Building with Jev★ 155
Agent skill for writing and improving programs that call Jev: question design, state structure, thresholds and diagnosing wrong answers.
Agent skillproduction Simon Willison's LLM plugin that adds Jev as a model for yes/no, choice and score questions from the command line.
PluginproductionPythonServer behind api.typesafe.pro, a free anonymous System One-compatible endpoint that forwards to TypeSafe on the operator's key.
Serviceproduction