jev-practice-speed
WebGL card game Speed against a Jev-powered CPU, showing Jev's decision latency and accuracy against a rule validator in real time.
Overview
JEV SPEED is a WebGL demo of the card game Speed played against a CPU whose brain is TypeSafe's Jev. Its purpose is to show Jev's decision speed and accuracy live. Each turn the CPU asks, for every combination of hand card and pile (up to 10), whether the card can be stacked as a Noul, all in parallel in one request, then asks a Choice for which move to play, plus a pressure Score from 0 to 3 that drives Jev's displayed mood.
The final verdict on rule legality is never left to Jev: a mechanical rules module checks every move, and illegal moves are rejected. This double structure feeds a HUD showing latency (p50, p95, min, max), per-candidate probabilities and agreement with the mechanical check, cumulative accuracy, false positives and negatives, token use and estimated cost. The key stays in the server process, and a mock mode with a visible badge runs without a key. It deploys on Cloudflare Workers.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Yes / no | Can this card be stacked on this pile? | yes · no |
| Choice | Which move should I play right now? | — |
| Score | pressure: how few options do you have? (0-3) | 0 · 1 · 2 · 3 |
How it works
- Build all hand-pile combinations
- Ask a Noul per combination, a move Choice and a pressure Score in one request
- Validate the chosen move with the mechanical rules
- Play it and update the HUD metrics
Strengths
- Live view of latency and accuracy
- Rules enforced in code, not by the model
- Zero runtime dependencies; mock mode without key
Caveats
- Mock mode is not representative of real accuracy
- Three.js loaded from a CDN on first run
Getting started
echo 'TYPESAFE_API_KEY=sk-...' > .env && npm start, then open http://localhost:5173At a glance
- Type
- App
- Status
- prototype
- Language
- JavaScript
- Runtime
- Browser (WebGL) with Node or Cloudflare Worker backend
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
A WebGL demo where you play the card game Speed against a CPU whose brain is TypeSafe AI's Jev. The whole point of the app is to measure and show Jev's decision speed and decision accuracy in real time.
logicrw/awesome-jev-projectsA WebGL demo where you play the card game Speed against a CPU whose brain is TypeSafe AI's Jev. The whole point of the app is to measure and show Jev's decision speed and decision accuracy in real time.
hellogumbo/awesome-jev
Frequently asked questions
Does Jev decide legality?
No. Jev predicts stackability, but a mechanical rules check makes the final call.
What does the HUD show?
Latency stats, per-move probabilities, agreement with the rules check, accuracy and cost.
Can I play without a key?
Yes, in mock mode, clearly marked in the HUD.
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