Although steps 6 and 7 are outlined separately in the manuscript, the implementation of the workflow requires these steps to be coupled. This is because the IBM RXN mapper is required to choose the most optimal species when there is more than one suitable candidate to meet the atom surplus on the RHS. The help species library is shown in Figure (a). In addition to cases where LHS species are insufficient in matching an atom surplus on the RHS, other sources of error include SMILES discrepancies in species (eg. ionic species that are lacking charges in exported SMILES from Reaxys®), charge imbalances, and invalid balancing results (eg. removing or moving reactants and products from one side to another). These reactions were all filtered out.