JUKE.

One paddle against three AI opponents

You0
40s
0AI
GPT-6 Luna
GPT-5.6 Luna
GPT-4.1 nano
Drag your paddle

Pip

GPT-6 Luna

Connecting
- ms$0.00000
Momo

GPT-5.6 Luna

Responses
Connecting
- ms$0.00000
Bibi

GPT-4.1 nano

Responses
Connecting
- ms$0.00000

Your game

Game mode

Three real models. $0.50 of API calls covered daily.

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How to play

Touch the rink to start. Move the white paddle with your mouse, finger or arrow keys. Hit the puck into any coloured goal and protect your own.

You play against all three opponents at once. First to 5 wins. After 40 seconds, the higher score wins.

Each opponent chooses its next move through a real API call. Its response time and cost appear beside its name.

Can a decision model keep up?

JUKE explores how API response time changes a game. Three models see the same kind of physical state and choose from five moves.

GPT-6 Luna
Decisions API · choice question. Returns one allowed move directly.
GPT-5.6 Luna
Responses API · structured JSON · reasoning set to none.
GPT-4.1 nano
Responses API · structured JSON.

The puck keeps moving while they decide. Their moves take effect when the response arrives. Costs use actual token usage.

The idea comes from decision models such as Jev by TypeSafe. This arena runs the three OpenAI models listed above.

Read the architecture ↗

Your daily play

keff covers up to $0.50 of model calls per browser each day. Playing is free.

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Add JUKE

Launch from your home screen. OpenAI mode needs an internet connection. Arcade works offline once the app has loaded.

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