Thalarch Android

Android lens

Prefer official current Android skills/tooling available in the environment for version-sensitive platform facts. Thalarch supplies scope control, regression safety, causal reasoning, routing, and proof discipline around them.

Preflight

Inspect:

• module graph;
• Gradle/AGP/Kotlin/version catalog;
• manifests;
• Compose/navigation/state patterns;
• Media3/session/service/player ownership when playback is involved;
• Room/repository/data-source boundaries when persistence is involved;
• locale/resource structure when user-facing text changes;
• CI build tasks;
• device/runtime requirements.

Do not upgrade toolchain or libraries unless the task requires it.

Specialist routing

Use the smallest relevant stack rather than loading every Android skill.

• Media3, ExoPlayer, MediaSession, MediaLibrarySession, Android Auto, queue/timeline, audio/video track selection, cache/preload/recovery, or audio-processing pipeline → thalarch-media3;
• Compose redesign/product UI/settings/media surfaces → thalarch-compose-ui, plus thalarch-design-system when visual direction needs extraction or re-articulation;
• fuzzy title/artist/catalog/provider identity resolution → thalarch-entity-matching;
• user-facing strings, locale resources, RTL, placeholder parity, translation completeness → thalarch-localization;
• a working subsystem where a narrow change could break adjacent behavior → thalarch-no-regression;
• measured/suspected CPU, allocation, memory, cache, build, or hot-path cost → thalarch-performance;
• Room/SQL query-shape and persistence work → thalarch-data-sql as needed;
• version-sensitive deprecations/API migrations → thalarch-source-grounding plus the Android deprecation playbook below.

No-Regression Contract

For playback, cache, persistence, sync, migration, concurrency, or other high-blast-radius surfaces, use thalarch-no-regression before mutation.

Capture the local must-preserve behaviors, the suspected problem, evidence state, intended action (AUDIT ONLY vs targeted mutation), and the verification needed.

A similar fix in another application is evidence to investigate, not evidence that this repository has the same defect.

Compose

Check:

• state ownership/stability;
• effects/lifecycle;
• recomposition-sensitive work;
• lazy keys;
• edge-to-edge/insets;
• adaptive behavior;
• touch targets/semantics;
• theme consistency;
• localization/truncation;
• RTL/AutoMirrored directional icons;
• font scaling;
• rendered behavior on the actual supported device classes.

For substantial Compose work, use thalarch-compose-ui rather than treating source review as visual proof.

Media/runtime

For Media3/playback/services inspect:

• lifecycle/session ownership;
• cancellation;
• buffering/retry;
• cache;
• queue/timeline invariants;
• audio focus;
• service process/state;
• resolver/network fallback ordering;
• audio-only vs video-capable selection;
• preload/recovery loops;
• DSP/audio-processor ordering when relevant.

Route substantial Media3 work to thalarch-media3.

Do not cure state bugs with arbitrary delays without evidence.

Performance and cache

When the task touches memory, cache, hot paths, playback churn, jank, or repeated work, read:

• references/android-performance.md

Audit for concrete work such as repeated regex compilation, collection scans, Room N+1 queries, full-cache enumeration, polling loops, listener/job leaks, oversized artwork, recomposition-heavy work, native/media allocation churn, or unnecessary video decoding during audio-only playback.

For a cache that currently works, combine thalarch-performance with thalarch-no-regression and presume its current semantics must be preserved until a defect/inefficiency is demonstrated.

Room and pagination

When a caller exposes paging (page / pageSize) and the backing collection can be large, trace the paging contract all the way to the data source. Read:

• references/room-pagination.md

Do not claim real pagination when the implementation loads the full dataset and truncates it after the fact. Preserve ordering, identity, filtering, and browsing semantics; test empty, partial,

1000-row, duplicate/ordering, and adjacent-page boundaries where relevant.

Deprecation migration

For compiler deprecations or override-signature warnings, read:

• references/deprecation-migration.md

Ground the exact installed dependency version, prove the official replacement, migrate minimally, and preserve runtime semantics. Do not use suppression as a substitute for a valid supported migration.

Localization

When new or changed user-facing text is introduced, use thalarch-localization to verify locale inventory, key and placeholder parity, natural domain terminology, layout expansion, and RTL.

A default-locale build does not prove translation completeness or unclipped UI.

Proof hierarchy

Compilation proves compilation only.

For runtime/UI behavior use, where available:

• targeted unit/integration tests;
• instrumentation;
• emulator/device interaction;
• Android Auto/head-unit/controller interaction when relevant;
• adb/log evidence;
• screenshots/recordings for visual claims;
• profiling/trace evidence for performance claims.

Keep unavailable runtime/device evidence explicitly UNVERIFIED rather than upgrading a source-only inference into PASS.