Mobile

Run unit tests and instrumentation tests for Canvas Android apps. Use when user mentions testing, running tests, JUnit, Espresso, or checking test results. Includes commands for Student, Teacher, and Parent apps.

Selects implementation strategy (vertical slice, horizontal, or hybrid) with risk assessment. Use when planning feature implementation.

実装戦略（垂直スライス、水平、ハイブリッド）をリスク評価で選択。機能の実装計画時に使用。

Applies type safety and error handling rules. Enforces no-any policy and type guards. Use when implementing TypeScript or reviewing types.

Use when adding/modifying database columns, encountering "FOREIGN KEY constraint failed", "no such column", "cannot add NOT NULL column" errors, or creating schema migrations for SQLite/GRDB/SQLiteData - prevents data loss with safe migration patterns and testing workflows for iOS/macOS apps

Use when choosing Core Data vs SwiftData, setting up the Core Data stack, modeling relationships, or implementing concurrency patterns - prevents thread-confinement errors and migration crashes

Use when working with ANY data persistence, database, storage, CloudKit, migration, or serialization. Covers SwiftData, Core Data, GRDB, SQLite, CloudKit sync, file storage, Codable, migrations.

Symptom-based energy troubleshooting - decision trees for 'app at top of battery settings', 'phone gets hot', 'background drain', 'high cellular usage', with time-cost analysis for each diagnosis path

Use when UI is slow, scrolling lags, animations stutter, or when asking 'why is my SwiftUI view slow', 'how do I optimize List performance', 'my app drops frames', 'view body is called too often', 'List is laggy' - SwiftUI performance optimization with Instruments 26 and WWDC 2025 patterns

Use when asking 'where should I store this data', 'should I use SwiftData or files', 'CloudKit vs iCloud Drive', 'Documents vs Caches', 'local or cloud storage', 'how do I sync data', 'where do app files go' - comprehensive decision framework for all iOS storage options

Use when implementing on-device AI with Apple's Foundation Models framework — prevents context overflow, blocking UI, wrong model use cases, and manual JSON parsing when @Generable should be used. iOS 26+, macOS 26+, iPadOS 26+, visionOS 26+

Use when you see 'actor-isolated', 'Sendable', 'data race', '@MainActor' errors, or when asking 'why is this not thread safe', 'how do I use async/await', 'what is @MainActor for', 'my app is crashing with concurrency errors', 'how do I fix data races' - Swift 6 strict concurrency patterns with actor isolation and async/await

Use when optimizing Swift code performance, reducing memory usage, improving runtime efficiency, dealing with COW, ARC overhead, generics specialization, or collection optimization

Use when implementing App Shortcuts for instant Siri/Spotlight availability, configuring AppShortcutsProvider, adding suggested phrases, or debugging shortcuts not appearing - covers complete App Shortcuts API for iOS 16+

Use when localizing apps, using String Catalogs, generating type-safe symbols (Xcode 26+), handling plurals, RTL layouts, locale-aware formatting, or migrating from .strings files - comprehensive i18n patterns for Xcode 15-26

Use when making app surface in Spotlight search, Siri suggestions, or system experiences - covers the 6-step strategy combining App Intents, App Shortcuts, Core Spotlight, and NSUserActivity to feed the system metadata for iOS 16+

Use when fixing VoiceOver issues, Dynamic Type violations, color contrast failures, touch target problems, keyboard navigation gaps, or Reduce Motion support - comprehensive accessibility diagnostics with WCAG compliance, Accessibility Inspector workflows, and App Store Review preparation for iOS/macOS

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

Use when Now Playing metadata doesn't appear on Lock Screen/Control Center, remote commands (play/pause/skip) don't respond, artwork is missing/wrong/flickering, or playback state is out of sync - provides systematic diagnosis, correct patterns, and professional push-back for audio/video apps on iOS 18+

Use when fixing or auditing ANY accessibility issue - VoiceOver, Dynamic Type, color contrast, touch targets, WCAG compliance, App Store accessibility review.