markuz89/minijev-snake

MiniJEV · Snake

A tiny decision model (≈0.5M parameters, 2 MB) that plays Snake on a 10×10 board. It is not a language model and generates no text. At each step it scores the available choices (move up, move down, move left, move right) and returns a calibrated probability for each one.

It is the first benchmark of MiniJEV. The same core (state + question + dynamic list of choices → choice + calibrated confidence) is used for text decisions in markuz89/minijev-general.

Results (200 games, 10×10, max score 97)

metric	value
average score	88.6
median score	97 (board filled)
games won (board filled)	73.5 %
deaths	19 %
stopped for starvation	7.5 %
fatal moves	0.02 % of decisions

For comparison, the search-based oracle the model was first distilled from scores 95 on average and wins 38 % of games. The model wins more often but has a lower average score.

Training pipeline:

1. Supervised distillation from the oracle.
2. DAgger.
3. PPO (two rounds, γ = 0.995, on an RTX 4090).
4. The choices were then renamed from UP/DOWN/… to move up/… without retraining. Only the choice encoder was re-fit, and the probabilities are identical (max difference 4e-7).

Usage

git clone https://huggingface.co/markuz89/minijev-snake && cd minijev-snake/code
pip install -e ".[train]"      # needs torch; ONNX export is available for torch-free inference

from minijev.inference.runtime import MiniJEV

dec = MiniJEV.load("..")                 # the cloned repo folder (or the repo id)
state = dec.task.example_states(1)[0]    # {"body": [...], "food": (x, y), "direction": ...}
d = dec.decide(state)                    # question and choices default to the Snake task
print(d.choice, d.confidence, d.scores)  # e.g. "move left" 0.999 {...}

Files

• model.safetensors: weights (no pickle)
• config.json: architecture, task config, calibration temperature, metrics
• code/: the minijev package and the Snake environment needed to run it

Limits

The model was trained only on 10×10 boards. Inputs are the grid channels of the MiniJEV Snake environment, and it is not a general game-playing agent.