Chemprop offers three modes for utilizing CGR with input reaction SMILES: "reac_diff," "prod_diff," and "reac_prod." These modes correspond to (1) the reactants plus the difference between the product and reactants, (2) the product plus the difference between the reactants and product, and (3) the direct joining of reactants and product, respectively. Previous studies by Heid and Green have reported that the "reac_diff" mode (reactant + difference) generally provides the best performance. Therefore, in the following analyses, we use the CGR in its default mode ("reac_diff") as shown in Figure . Example of a condensed graph of reaction representation using the "reac_diff" mode. In the schematic, "x" denotes nodes, "e" represents edges in the GNN, and "r" and "p" correspond to reactant(s) and product(s), respectively.