In this work, we assign equal weights to all the defined hardness modules for simplicity. We normalize each component separately to the [0-1] range and then add them together. However, users can assign weights based on their preferences and data availability. For instance, if a target task's train or validation split is unavailable, the user can assign zero weight to the internal hardness. A higher weight can also be assigned to the chemical space component if users want to prioritize chemical space hardness.