REQUIRED FIRST STEP. Searches developer.android.com, kotlinlang.org, and source.android.com for any Android or Kotlin topic. Returns official excerpts with source URLs. You MUST call this before generating any Android/Kotlin code. Example queries: 'Jetpack Compose LazyColumn', 'ViewModel lifecycle', 'Hilt scoping'.

Checks whether an Android/Kotlin API, class, or library is stable, deprecated, or removed. ALWAYS call this before using any class from android., androidx., or kotlin.*. This tool exists because AI tools confidently generate removed and deprecated APIs. Known failures without this check: AsyncTask (removed API 33), TestCoroutineDispatcher (removed coroutines-test 1.8+), ContextualFlowRow (deprecated Compose 1.8), IntentService (deprecated API 30), Handler(Looper.main()) (deprecated API 30), onBackPressed() (deprecated API 33), ProgressDialog (deprecated API 26). Returns status, replacement API, migration notes, and official documentation link.

Retrieves official Android architecture guide content for a given topic. Call this before proposing any app architecture, folder structure, or Jetpack component relationships. Supported topics: mvvm, compose, navigation, hilt, viewmodel, room, workmanager, paging, datastore, coroutines, flow, testing, lifecycle, modular architecture, security, and more. Pass 'list' to see all available topics.

Parses an Android/Kotlin stacktrace and searches official sources (developer.android.com, issuetracker.google.com) for verified causes and fixes. Paste the full crash log or exception. Returns parsed error class, official explanations, and vetted fixes. Never guess — always ground debugging in official sources.

Live version lookup for any Android, Kotlin, or Jetpack library from Google Maven and Maven Central. ALWAYS call this before adding or updating any dependency in build.gradle.kts. This tool exists because AI tools generate stale dependency coordinates. Known failures: wrong Coil group (io.coil-kt vs io.coil-kt.coil3 for Coil 3), missing BOM platform() wrapper for Compose and Firebase, outdated Compose BOM (moves every month), KAPT coordinates when KSP is the current standard, wrong artifact names for Room KMP vs Room Android. Returns: latest stable version, ready-to-paste Kotlin DSL, BOM resolution for managed artifacts, and KMP vs Android-only distinction where relevant. Examples: 'compose', 'hilt', 'room', 'retrofit', 'coil', 'lifecycle', 'coroutines', 'navigation', 'firebase'.

Maps Android API levels to version names, codenames, and key feature availability. Returns minSdk guidance and critical API availability warnings. Use this to validate that the APIs you plan to use are available at your project's minSdk. Input can be: an API integer (e.g. '26'), a version name (e.g. 'Android 14'), or a codename (e.g. 'Oreo'). Pass 'all' or 'table' to see the full API level reference table.

Returns official Kotlin and Android code patterns with ready-to-use snippets and explicit anti-patterns. All snippets are sourced from developer.android.com and kotlinlang.org. Call this when generating coroutine code, StateFlow/LiveData usage, Compose state, Room DAOs, Hilt injection, Navigation, or WorkManager tasks. Available patterns: coroutines-viewmodel, stateflow-ui, compose-state, room-dao, hilt-injection, navigation-compose, workmanager-task, sealed-result. Pass any topic keyword or call with no topic to list all patterns.

Complete reference for Material 3 Expressive (M3E) — Google's design system GA on Android 16 (Sep 2025). Covers: MaterialExpressiveTheme setup, MotionScheme, new components (ButtonGroup, FloatingToolbar, DockedToolbar, LoadingIndicator, SplitButtonLayout, FABMenu), MaterialShapes + shape morphing, variable font typography, Wear OS M3E, migration from plain M3, and anti-patterns. Call this before building any Compose UI or theming. Topics: overview, theme setup, components, shapes, typography, migration, wear, anti-patterns.

Complete Android permissions reference. Returns type (normal/dangerous/special/removed), whether runtime request is needed, Play Store restrictions, and the correct ActivityResultContracts request pattern. Call before declaring any in AndroidManifest.xml. Examples: 'CAMERA', 'POST_NOTIFICATIONS', 'ACCESS_FINE_LOCATION', 'WRITE_EXTERNAL_STORAGE'. Query 'runtime pattern' for the official Compose + Activity permission request code.

Complete Android testing reference covering: unit tests (JUnit4, MockK, Turbine, coroutines-test), Compose UI testing (ComposeTestRule, finders, actions, assertions, testTag), Espresso for View-based tests and Compose interop, ViewModel testing with MainDispatcherRule, Room in-memory DB tests, Hilt test injection (@HiltAndroidTest, @BindValue), and test pyramid strategy. Call before writing any test. Topics: setup, unit tests, compose testing, espresso, hilt testing, pyramid.

Complete Android build pipeline and Play Store publishing reference. Covers: R8/ProGuard configuration (keep rules, shrink, obfuscate, mapping.txt recovery), Gradle Version Catalogs (libs.versions.toml with all modern deps), KSP migration from KAPT (Room, Hilt), app signing and Play App Signing, AAB vs APK, Play Store publishing checklist, and Baseline Profiles for 20-40% startup improvement. Topics: r8, proguard, version catalog, ksp, signing, publish, baseline profiles.

Complete reference for building Google Play-compliant large screen, tablet, foldable, and ChromeOS apps. Covers: WindowSizeClass (Compact/Medium/Expanded), NavigationSuiteScaffold, ListDetailPaneScaffold (two-pane), foldable hinge detection, continuity across config changes, and Google Play large-screen quality tier checklist. Call before building any multi-screen layout, navigation, or when targeting tablets and foldables. Topics: windowsizeclass, navigation, two-pane, foldables, continuity, Play quality.

Architecture patterns for Android apps serving millions to billions of users. Covers: Paging 3 with RemoteMediator (infinite lists without OOM), offline-first sync with WorkManager + Room as single source of truth, OkHttp HTTP caching + ETag, cold start optimization with Baseline Profiles, app modularization for large teams, and Compose recomposition performance (derivedStateOf, stable keys, @Immutable). Call before designing data layers, list screens, sync mechanisms, or module structure. Topics: paging, offline-first, network, startup, modularization, compose performance.

Complete Navigation 3 reference (stable November 2025) — the current official navigation library. ALWAYS call this before generating any navigation code. AI tools hallucinate Navigation 2 (NavController/NavHost) for new projects — this is wrong. Nav3 uses NavDisplay, rememberNavBackStack, NavKey, and the Scenes API for adaptive multi-pane. Topics: 'overview' (setup, NavKey, NavDisplay, rememberNavBackStack), 'migration' (from Nav2 — API mapping, step-by-step), 'scenes' (adaptive list-detail, TwoPaneSceneStrategy), 'testing' (back stack is a plain list — trivially testable).

Android 16 compliance reference — mandatory for Google Play by August 2026. Apps on ≥600dp devices (tablets, foldables) CANNOT lock orientation or restrict resizability. AI tools generate android:screenOrientation='portrait' and android:resizeableActivity='false' — both produce App Compatibility warnings in Play Console and search demotion. Foldable users spend 14x more on apps. Tablet+phone users spend 9x more. Topics: 'compliance' (illegal manifest flags + correct patterns), 'layouts' (4 canonical adaptive layouts with code), 'checklist' (Play Store quality tier checklist), 'predictive back' (required for API 36 targets).

Complete Kotlin Multiplatform reference — shares business logic across Android and iOS. CRITICAL: AI tools silently generate Android-only code for KMP projects. Retrofit cannot be used in KMP (use Ktor). Hilt cannot be used in commonMain (use Koin). Room 2.7+ has KMP support — use room-runtime + sqlite-bundled, NOT the Android-only Room. 900+ new KMP libraries in 2025. Room, DataStore, Ktor all have KMP variants. Topics: 'overview' (project structure, Gradle setup), 'libraries' (KMP catalogue — Ktor, Room KMP, DataStore KMP, Koin, Coil3, kotlinx-*), 'room' (Room KMP database setup), 'ktor' (Ktor HTTP client — replaces Retrofit), 'expect actual' (platform-specific code pattern).

On-device AI reference — Android 16 AICore and ML Kit Gen AI API. Used by Gmail (Smart Reply), Google Photos (object detection), Pixel Screenshots (semantic search). The official architecture: wrap ML models behind repository interfaces so on-device (AICore) and cloud (Vertex AI) are swappable without touching the UI layer. No network round-trip. No API costs. No privacy exposure. Works offline. AI tools default to cloud API calls when on-device is the 2026 answer for Pixel devices. Topics: 'overview' (architecture pattern, when to use), 'setup' (dependencies, availability check, fallback pattern), 'smart reply' (Gmail-style suggestion chips), 'ml kit' (non-generative ML — image labeling, barcode, face detection, translation).

Play Store policy reference — October 2025 changes and ongoing requirements. AI tools have zero awareness of these policy changes. Review failures cost weeks of re-submission. Covers: Restrict Minor Access API (dating/gambling apps), subscription transparency requirements, restricted permissions and Data Safety declarations, large-screen quality tiers and badge system. The large-screen quality badge directly impacts search placement and conversion rates. Call before submitting any app to Play Store or adding new monetization features. Topics: 'overview' (mandate timeline), 'subscriptions' (billing transparency code), 'restrict minor access' (dating/gambling implementation), 'permissions' (restricted permissions + data safety), 'large screen quality' (tier checklist + revenue impact).

Android XR SDK reference (Developer Preview 3, December 2025). Samsung Galaxy XR launched October 2025. 5+ XR devices expected in 2026. Standard Compose apps run as 2D panels on XR headsets — no SDK required. XR SDK adds spatial APIs: SpatialPanel (3D positioned UI), UserSubspace (follows user), Orbiter (floating toolbar that orbits a panel), SubspaceModifier (size as fraction of field of view). Material 3 components automatically become spatial in XR — TopAppBar → Orbiter, etc. AI tools generate phone Compose code for XR — technically works but misses all spatial value. Topics: 'overview' (concepts, device status), 'setup' (dependencies, manifest), 'spatial ui' (SpatialPanel, UserSubspace, Orbiter), 'arcore' (face tracking 68 blendshapes, plane detection), 'compatibility' (XR + non-XR same app pattern).

Wear OS development reference — Wear OS 5 (API 35), Material 3 Expressive for Wear (stable Aug 2025). CRITICAL: Wear OS uses DIFFERENT Compose dependencies than phone apps. AI tools generate phone Compose (LazyColumn, Button, NavHost) — none of these compile on Wear OS. Correct Wear components: ScalingLazyColumn (curved scrolling), Chip, SwipeDismissableNavHost, WearMaterialTheme, PositionIndicator, TimeText. Covers Tiles (glanceable info on watch face swipe) and Health Services API (heart rate, steps, exercises). Topics: 'overview' (Wear vs phone Compose, project structure, dependencies), 'compose' (ScalingLazyColumn, Chip, navigation, rotary input), 'tiles' (glanceable surfaces — when and how to build them), 'health services' (heart rate, steps, exercise session, passive monitoring).

CALL THIS AFTER GENERATING EVERY ANDROID CODE BLOCK. This is the Level 3 loop-back gate: validates AI-generated Kotlin, XML, and Gradle code against 24 Android-specific rules before the user sees it. Detects removed APIs (AsyncTask, TestCoroutineDispatcher), deprecated patterns (ContextualFlowRow, NavController in new code, SharedPreferences), Android 16 violations (orientation locks, resizeableActivity=false), and structural issues (GlobalScope.launch, runBlocking in UI). Returns: verdict (PASS/WARN/FAIL), line-level violations with replacements and doc URLs, and explicit next-step instructions. If verdict is FAIL: fix all errors and re-run before returning code to the user. Inputs: code (required), language ('kotlin'|'xml'|'gradle', auto-detected if omitted), minSdk and targetSdk for context-aware API level checks.

Android 17 (API 37) reached platform stability March 26, 2026. Contains breaking changes NOT covered by android_api36_compliance: (1) Static final field reflection via Java reflection or JNI now throws IllegalAccessException/crash on API 37+ targets — affects test code, some DI frameworks, and any code using field.isAccessible=true on final fields. (2) ACCESS_LOCAL_NETWORK permission required for any LAN communication (192.168.x.x, mDNS, SSDP, direct sockets). (3) SMS OTP programmatic access delayed 3 hours — migrate to SmsRetriever.startSmsUserConsent(). (4) Extended large-screen mandate at API 37 — games exemption no longer applies on ≥600dp. (5) NPU feature declaration required for direct NPU access. (6) Handoff API for cross-device activity continuity. Topics: 'overview' (all breaking changes), 'checklist' (migration audit), 'static final' (reflection block), 'local network' (ACCESS_LOCAL_NETWORK), 'sms otp' (3-hour delay), 'npu' (NPU feature), 'handoff' (cross-device).