The same issue was observed in the sole instance in which an incorrect assignment was made within the polyamide class. In the example shown in Fig. ), the ring in the precursor of Nylon 3 was incorrectly sanitized and generated a false structure with the amide bond intact. In general, the opening of the heterocyclic ring is the most significant challenge of the validation process. Future extensions of the HTA algorithm will require a robust sanitization process for complex monomers, such as cyclic precursors. A potential pathway could be the representation of precursor molecules as graphs during the sanitization phase, with atoms designated as nodes and bonds as edges. The graph representation would allow for the assignment of the bond to be broken, indicated by the edges to be deleted. In addition, atoms or groups of atoms could be deleted or added by indicating the respective nodes. For enhancing the accuracy of the head and tail assignment, we suggest considering the HOMO and LUMO orbitals as the nucleophilic and electrophilic sites, respectively. In addition, considering the comprehensive chemical information provided by the frontier orbitals may be beneficial.