Citations

Reference — PHPickerViewController, PHPickerConfiguration, PhotosPicker, PhotosPickerItem, Transferable, PHPhotoLibrary, PHAsset, PHAssetCreationRequest, PHFetchResult, PHAuthorizationStatus, limited library APIs

Use when implementing SwiftUI animations, understanding VectorArithmetic, using @Animatable macro, zoom transitions, UIKit/AppKit animation bridging, choosing between spring and timing curve animations, or debugging animation behavior - comprehensive animation reference from iOS 13 through iOS 26

Reference — Comprehensive Apple Human Interface Guidelines covering colors (semantic, custom, patterns), backgrounds (material hierarchy, dynamic), typography (built-in styles, custom fonts, Dynamic Type), SF Symbols (rendering modes, color, localization), Dark Mode, accessibility, and platform-specific considerations

Reference — Complete SwiftUI adaptive layout API guide covering ViewThatFits, AnyLayout, Layout protocol, onGeometryChange, GeometryReader, size classes, and iOS 26 window APIs

Use for Core Location API reference - CLLocationUpdate, CLMonitor, CLServiceSession, authorization, background location, geofencing

Reference — Comprehensive SwiftUI navigation guide covering NavigationStack (iOS 16+), NavigationSplitView (iOS 16+), NavigationPath, deep linking, state restoration, Tab+Navigation integration (iOS 18+), Liquid Glass navigation (iOS 26+), and coordinator patterns

TextKit 2 complete reference (architecture, migration, Writing Tools, SwiftUI TextEditor) through iOS 26

Reference — SwiftUI stacks, grids, outlines, and scroll enhancements through iOS 26

Use when implementing 'iCloud Drive', 'ubiquitous container', 'file sync', 'NSFileCoordinator', 'NSFilePresenter', 'isUbiquitousItem', 'NSUbiquitousKeyValueStore', 'ubiquitous file sync' - comprehensive file-based iCloud sync reference

Apple platform typography reference (San Francisco fonts, text styles, Dynamic Type, tracking, leading, internationalization) through iOS 26

Complete background task API reference - BGTaskScheduler, BGAppRefreshTask, BGProcessingTask, BGContinuedProcessingTask (iOS 26), beginBackgroundTask, background URLSession, with all WWDC code examples

Reference — Comprehensive Network.framework guide covering NetworkConnection (iOS 26+), NWConnection (iOS 12-25), TLV framing, Coder protocol, NetworkListener, NetworkBrowser, Wi-Fi Aware discovery, and migration strategies

Reference — AVCaptureSession, AVCapturePhotoSettings, AVCapturePhotoOutput, RotationCoordinator, photoQualityPrioritization, deferred processing, AVCaptureMovieFileOutput, session presets, capture device APIs

Create architectural decision records (ADRs), system documentation, API documentation, and operational runbooks. Use when capturing design decisions, documenting system architecture, creating API references, or writing operational procedures.

Requirement gathering techniques, stakeholder analysis, user story patterns, and specification validation. Use when clarifying vague requirements, resolving conflicting needs, documenting specifications, or validating requirements with stakeholders.

Systematic code refactoring while preserving all external behavior. Use when identifying code smells, planning refactoring sequences, executing safe structural improvements, or validating behavior preservation. Includes code smell catalog (reference.md) and refactoring execution protocol.

Create HTML technical documentation with code blocks, API workflows, system architecture diagrams, and syntax highlighting. Use when users request technical documentation, API docs, API references, code examples, or developer documentation.

Store key-value data globally with Cloudflare KV's edge network. Use when: caching API responses, storing configuration, managing user preferences, handling TTL expiration, or troubleshooting KV_ERROR, 429 rate limits, eventual consistency, or cacheTtl errors.

Build document Q&A and searchable knowledge bases with Google Gemini File Search - fully managed RAG with automatic chunking, embeddings, and citations. Upload 100+ file formats (PDF, Word, Excel, code), configure semantic search, and query with natural language. Use when: building document Q&A systems, creating searchable knowledge bases, implementing semantic search without managing embeddings, indexing large document collections (100+ formats), or troubleshooting document immutability errors (delete+re-upload required), storage quota issues (3x input size for embeddings), chunking configuration (500 tokens/chunk recommended), metadata limits (20 key-value pairs max), indexing cost surprises ($0.15/1M tokens one-time), operation polling timeouts (wait for done: true), force delete errors, or model compatibility (Gemini 2.5 Pro/Flash only).

Clerk auth with API Keys beta (Dec 2025), Next.js 16 proxy.ts, API version 2025-11-10 breaking changes, clerkMiddleware() options, webhooks, and component reference. Use when: API keys for users/orgs, Next.js 16 middleware filename, troubleshooting JWKS/CSRF/JWT errors, webhook verification, or testing with 424242 OTP.