Someone got Jev to play Super Mario Bros

Branko Trcek @BrankotrcekOriginally posted 2026.09.21

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JEV is f*cking INSANE. Someone got it to play Super Mario Bros. The interface shows it choosing between controller actions: move right, jump, run, or wait. One visible decision: “right jump.” 89 ms latency. 83% confidence. Fast inference + structured outputs, applied to a game where the next move actually matters. Mario makes the idea easy to understand: pick an action, execute it, then respond to what happens next. Now imagine that same decision loop inside a browser agent.

This post quotes another post: “23-minute Jev tutorial: three decision-making AI builds”