macOS menu bar app that reads IOKit to surface per-port USB-C cable specs, charging diagnostics, and e-marker data in plain English.
Key Takeaways
Pulls data from three IOKit service families: AppleHPMInterfaceType10/11, IOPortFeaturePowerSource, and IOPortTransportComponentCCUSBPDSOP – no private APIs or helper daemons.
Shows cable speed (USB 2.0 up to 80 Gbps), current rating (3A/5A), PDO list with live negotiated profile highlighted, and connected device identity via PD Discover Identity.
Charging bottleneck banner pinpoints whether the cable, charger, or Mac battery state is limiting power delivery.
E-marker data only appears for marked cables; most sub-60W cables are unmarked. PD 3.2 EPR variants not yet fully covered.
Universal binary (arm64 + x86_64), notarized, requires macOS 14 Sonoma. Not App Store eligible because App Sandbox blocks the required IOKit reads.
Hacker News Comment Review
One user reports both USB ports showing the same connected devices regardless of what is physically attached, suggesting a possible port-aggregation bug in the device identity logic.
Linux interest surfaced immediately, with a pointer to lsucpd on GitHub as a potential basis for a similar PD-aware wrapper around lsusb.
