ipatool is a cross-platform command-line tool that acts as an unofficial Apple App Store client. It enables searching, purchasing, and downloading iOS/iPadOS/tvOS/watchOS/visionOS/macOS applications and packages directly from Apple's servers. The tool implements Apple's private SAP authentication and signing protocol by emulating Apple's StoreAgent binary in-process using the Unicorn CPU emulator, allowing it to generate kbsync blobs and decrypt macOS packages. It also includes low-level parsers for Apple's proprietary formats (AEA encrypted archives, APFS filesystems, dyld shared caches) to extract assets from macOS restore images. The architecture is modular: a CLI layer (using cobra) dispatches to domain logic in pkg/appstore, which relies on a generic HTTP client (pkg/http), keychain storage (pkg/keychain), and platform abstractions (pkg/util). An MCP (Model Context Protocol) server subcommand exposes the same functionality over stdio. The codebase is heavily tested with unit and integration tests, and CI builds for macOS, Linux, Windows, and iOS. While primarily an application, it contains significant reverse-engineering and protocol-analysis components, giving it a hybrid character.