The route to getting the interaction details between two chains from PDBsum data shown in the notebooks here gets used in the pipeline for the notebook Report if residues interacting with a specific chain have equivalent residues in an hhsuite-generated alignment that can be run in launches from the hhsuite3-binder. There is a version built on that which uses snakemake to process several combinations of structures and chains all once and make a report for each desired pair that also relies on this path.