Apart from the base prompts and prompts for guided generation, we consider three additional prompts, described in Table , that allow us to control the extent of molecular modification and similarity with the given parent molecules. These prompts use verbal descriptors such as "barely similar (very low Tanimoto similarity)", "marginally similar (low Tanimoto similarity)", and "moderately similar (moderate Tanimoto similarity)" to describe the extent of similarity compared to the parent SMILES.