This is basically a map to Apple's developer documentation for iOS and macOS frameworks. It gives you local indexes for SwiftUI, UIKit, Core Animation, XCTest, HealthKit, Combine, SwiftData, and a few others so you can grep for APIs without fetching full docs every time. The indexes range from 3KB for Observation to 1.8MB for UIKit, and they include paths you can use to pull detailed pages from the sosumi.ai Markdown mirror when you need them. It's a sensible starting point if you're writing Swift code and need to check what exists in a framework before diving into specific documentation pages.
npx skills add https://github.com/vabole/apple-skills --skill apple-docs-index