If you're building macOS token driver extensions or integrating hardware security tokens with the system keychain, this covers the entire CryptoTokenKit stack. You'll find concrete implementations for TKTokenDriver subclasses, smart card APDU communication, PIN authentication flows, and how to expose token-backed keys as standard keychain items. The architecture split is clear: token extensions run macOS-only to bridge hardware to the system, while client apps on iOS 14+ can query those keychain items. Most useful if you're writing drivers for specific smart cards or USB tokens rather than just consuming existing ones. The session management and certificate authentication patterns are production-ready, not just API surface documentation.
npx skills add https://github.com/dpearson2699/swift-ios-skills --skill cryptotokenkit