j. JEV / REWARD ARCADE
OPEN EXPERIMENT GitHub ↗
REINFORCEMENT LEARNING, WITH A JUDGE

Let JEV judge.
Let the agent learn.

A tiny agent. A world to figure out. Every move becomes a lesson.
Watch a reward signal turn trial and error into a winning run.

OBSERVEACTJUDGELEARN
One decision at a time.
RULES DEMORecorded CPU training · deterministic judge · no JEV API callsREPLAY / SEED 7
01 / THE PLAYGROUND

Key Quest 9 × 7

TRAINED POLICY
STEP 00FIND THE KEY
Agent Key Exit LavaCollect the key. Avoid lava. Reach the exit.
04 / THE LEARNING CURVE

Practice leaves a trace.

Last 20 episodes · success
EXPLORATION ε 0.04350 EPISODES
05 / THE RESULT

Same world.
Better decisions.

BEFORE
AFTER

Success on 60 evaluation episodes, same seeds and map. Evaluation makes no judge calls.

UNDER THE HOOD

The judge supplies the reward. The agent learns the actions. Tabular Q-learning updates from the judge’s outcome probabilities. JEV receives structured state, including computed route distances; the agent sees only position and key possession. This is a small, inspectable experiment—not a pixel-based or general-game benchmark.

About JEV Score ↗