Is this an official TypeSafe product I can run in production?

No. The README states it is an independent community project, not an official TypeSafe product or production harness, and a typed answer is not a claim that the answer is correct.

What do I actually need installed to run it locally?

Node 22.3 or newer with the pinned pnpm from package.json, pnpm install with frozen lockfile, and pnpm dev on port 3042. You can browse and edit examples without a key; Live Jev controls need TYPESAFE_API_KEY.

How do A/B comparisons avoid inventing a difference?

Run example makes one evaluation request; Compare A/B makes two with one declared input difference and a preview of the change. A missing comparison field disables comparison rather than inventing one.

How is this different from the original playground repo?

It builds on the original example library and Python foundation with a Next.js interface and interactive prototypes. Original credit and MIT license are retained, and the catalog lives in web/catalog.json packs.

How do I keep the API key out of the repo?

The recommended route keeps it in 1Password and launches through pnpm dev:op. .env.1password is committed but holds a reference rather than a secret, TYPESAFE_API_KEY="op://Development/Jev API Key/password", which op run expands into the process environment at launch. That needs 1Password CLI 2.x, unlocked. Verify with curl -s localhost:3042/api/health, and remember a shell-provided variable beats .env.local.

How is the playground laid out, and what happens to old links?

Five sections, each with its own page: Language and data, Agents and workflows, Code and governance, Games and simulations, and the Arcade, with every workspace nested under its section, such as /language/jev-chat. Older flat links such as /jev-chat or /chess redirect permanently, query strings included, and the route map in lib/routes.ts feeds both the navigation and the redirects so the two cannot drift apart.

Where do my drafts and exported examples actually live?

Custom examples and drafts persist in browser storage for that origin, and results are not restored after a refresh. Export library and Import move examples between browsers, with imported id collisions becoming copies, and portable browser exports use an examples array rather than the repository catalog format. The README warns that exported input may contain private text, so read a file before you share it.

CommunityJev Demos & Experiments

TypeSafe AI Playground — BunsDev

Independent community Next.js playground for Jev experiments: editable typed questions, A/B input comparisons, conversation routing, document extraction, code-policy review, plus game and simulation workspaces.

See highlights

Open github.com

Stars: 24
Language: TypeScript
License: MIT
Published by: Community
Author: BunsDev
Last verified: Oct 2026

BunsDev/typesafe-ai-playground

Organization repository on GitHub

View on GitHub

Community TypeSafe AI playground: 110 use cases, games, dilemmas and model challenges, with editable prompts, A/B comparisons and a mobile-friendly UI.

Forks: 7
Last pushed: Updated Oct 2026

Repo stats from the GitHub API, cached Oct 2026.Homepage

About this project

A community playground for TypeSafe AI's Jev: edit classification experiments, compare A/B inputs, route conversations, extract document fields, inspect code-policy decisions, and explore games and simulations built around typed model outputs. Small experiments. Clear decisions. This is an independent community project, not an official TypeSafe AI product, production agent harness, or claim that a typed answer is correct.

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

Tagscommunity jevbest catalog-import

Works forJev for Classification

Used inJev for Software & DevTools

Languages: TypeScript

Highlights

Five sections for language, agents, governance, simulations, and arcade, with redirects from old flat routes.
Run examples and declared A/B pairs side by side, with drafts and library exports kept in browser storage.
Browse and mocked demos work without a key; controls labeled Live Jev need TYPESAFE_API_KEY.
Local solver and simulation paths plus server-side Z3 checks and labeled baselines for comparison.

Watch out

A single run is not a validated accuracy, fairness, or consistency benchmark. Puzzle notes are teaching aids and subjective judgments have no universal answer key. Custom drafts live in browser storage for that origin. 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.

Other listings of this project

Forks and copies of this project in the directory. This entry is the canonical one.

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