Cable Detective — what's actually plugged into each port.

Cable Detective is a macOS app that reads the I/O Kit registry to show what USB-C, Thunderbolt, and MagSafe ports are doing. It provides details on power direction, DisplayPort lane state, and cable identity without requiring a subscription or cloud access. The app helps identify issues like slow charging, display connectivity problems, and counterfeit cables by decoding e-marker data and negotiated power contracts. It also includes an on-device AI layer for plain-English explanations and supports Apple Silicon Macs running macOS 14 or later.