Run First Aid and a fault comes back as warning: inode (id 402194151) — an identifier, with no path and no name attached. Howard Oakley walks the resolution both directions, and the reason the number is what APFS hands you is the good part: a file keeps its inode for as long as it stays on the volume, however you rename it or wherever you drag it. He also shows how to tell whether a given file lives on the System or the Data volume.