macOS communicates with Kindles over USB in two distinct ways depending on the device generation. Confirm which workflow applies to you before starting the jailbreak.
Recent Kindle models with USB-C ports expose their storage over MTP (Media Transfer Protocol). macOS does not ship with native MTP support, so you must install an additional utility.
Required Software: Amazon USB File Transfer
Older Kindles with micro-USB ports expose their storage as classic USB Mass Storage. macOS supports this natively, so no additional software is required.
Confirming USB access before starting prevents mid-jailbreak interruptions caused by missing MTP support.