AGENTS.android.md — Android / Jetpack Compose

Additive to ../AGENTS.md and AGENTS.kotlin.md. Android-specific rules only.

Build and check

./gradlew ktlintCheck detekt                # must pass
./gradlew :feature:<module>:testDebugUnitTest
./gradlew assembleDebug                     # only if you touched build config

Jetpack Compose rules

• Composables are stateless and take a state object plus lambdas. Hoist state to the ViewModel.
• No business logic, no LaunchedEffect doing network calls, in a Composable.
• Collect ViewModel flows with collectAsStateWithLifecycle(), not collectAsState().
• Every new component in core/designsystem needs a @Preview and must consume design tokens, never hardcoded Color(0xFF...) or dp values that duplicate a token.
• Use existing components before adding a new one. If you add one, note in the PR which existing component you considered and why it did not fit.
• Modifier is always the first optional parameter and is passed through.
• User-facing text comes from string resources, never literals. Icons that act get a contentDescription; decorative ones get null.
• New navigation destinations use type-safe @Serializable routes, not strings.

Android rules

• A ViewModel exposes one StateFlow<UiState>. No LiveData in new code.
• No Activity, Fragment or View context held in a ViewModel or singleton. If you need a Context, inject the application context.
• Views collect flows inside repeatOnLifecycle, never in a bare lifecycleScope.launch.
• A new permission in AndroidManifest.xml needs a stated reason in the PR.

Testing

• Paparazzi or screenshot tests for design system components. Compose UI tests (createComposeRule) for interaction.
• Kotlin testing rules, including the bug-fix rule, are in AGENTS.kotlin.md.

Anti-patterns seen in this repo

• Mixed Flow/LiveData in the same feature. New code is Flow.
• Blocking calls inside init {} of a ViewModel.