Goldilocks CGCNN representation model

A crystal graph convolutional neural network classifier used by Goldilocks to estimate whether a periodic material is metallic. It was trained against Materials Project is_metal labels from an October 2025 snapshot. Class 0 denotes insulator and class 1 denotes metal.

The record includes the PyTorch Lightning checkpoint, its atom embedding table, and sidecar documentation containing the graph feature contract and checksums.