diff --git a/packages/capture-kit/package.json b/packages/capture-kit/package.json
index 0b2ba0e64..063685d2c 100644
--- a/packages/capture-kit/package.json
+++ b/packages/capture-kit/package.json
@@ -46,6 +46,10 @@
       "types": "./src/screenshot-diff-pixels.ts",
       "default": "./src/screenshot-diff-pixels.ts"
     },
+    "./snapshot-desktop-projection": {
+      "types": "./src/snapshot-desktop-projection.ts",
+      "default": "./src/snapshot-desktop-projection.ts"
+    },
     "./snapshot-occlusion": {
       "types": "./src/snapshot-occlusion.ts",
       "default": "./src/snapshot-occlusion.ts"
diff --git a/packages/capture-kit/src/snapshot-desktop-projection.test.ts b/packages/capture-kit/src/snapshot-desktop-projection.test.ts
new file mode 100644
index 000000000..768f31693
--- /dev/null
+++ b/packages/capture-kit/src/snapshot-desktop-projection.test.ts
@@ -0,0 +1,42 @@
+import { expect, test } from 'vitest';
+import fs from 'node:fs';
+import path from 'node:path';
+import { scopeSnapshotNodes } from './snapshot-desktop-projection.ts';
+
+test('scopeSnapshotNodes agrees with every golden scope-policy table case', () => {
+  const cases = JSON.parse(
+    fs.readFileSync(
+      path.resolve(import.meta.dirname, '../../../contracts/fixtures/snapshot-scope-policy.json'),
+      'utf8',
+    ),
+  ) as Array<{
+    name: string;
+    scope: string;
+    nodes: Array<{
+      depth: number;
+      label?: string;
+      value?: string;
+      identifier?: string;
+      presented?: boolean;
+    }>;
+    expectedSubtreeIndexes: number[];
+  }>;
+  expect(cases.length).toBeGreaterThan(0);
+  for (const fixture of cases) {
+    const parents: number[] = [];
+    const nodes = fixture.nodes.map((node, index) => {
+      parents.length = node.depth;
+      const parentIndex = node.depth > 0 ? parents[node.depth - 1] : undefined;
+      parents[node.depth] = index;
+      return { ...node, index, parentIndex, rect: { x: index, y: 0, width: 1, height: 1 } };
+    });
+    const scoped = scopeSnapshotNodes(nodes, fixture.scope, (range) =>
+      nodes.slice(range.start, range.end).some((node) => node.presented !== false),
+    );
+    expect(
+      scoped.map((node) => node.rect?.x),
+      fixture.name,
+    ).toEqual(fixture.expectedSubtreeIndexes);
+    if (scoped.length > 0) expect(scoped[0]?.depth, fixture.name).toBe(0);
+  }
+});
diff --git a/packages/capture-kit/src/snapshot-desktop-projection.ts b/packages/capture-kit/src/snapshot-desktop-projection.ts
new file mode 100644
index 000000000..0d5b0139e
--- /dev/null
+++ b/packages/capture-kit/src/snapshot-desktop-projection.ts
@@ -0,0 +1,75 @@
+import type { RawSnapshotNode } from '@agent-device/kernel/snapshot';
+import type { SnapshotOptions, SnapshotResult } from '@agent-device/contracts/interactor-types';
+import {
+  findSnapshotScopeRange,
+  normalizeSnapshotScope,
+  reindexSnapshotNodes,
+} from '@agent-device/contracts/snapshot-scope';
+
+const INTERACTIVE_ROLE_TOKENS = [
+  'button',
+  'menu',
+  'textfield',
+  'searchfield',
+  'checkbox',
+  'radio',
+  'switch',
+] as const;
+
+export function shapeDesktopSurfaceSnapshot(
+  data: SnapshotResult,
+  options: Pick<SnapshotOptions, 'depth' | 'interactiveOnly' | 'scope'>,
+): SnapshotResult {
+  let nodes = data.nodes ?? [];
+  if (options.scope) {
+    nodes = scopeSnapshotNodes(nodes, options.scope, (range) =>
+      options.interactiveOnly
+        ? nodes.slice(range.start, range.end).some(isInteractiveSnapshotNode)
+        : true,
+    );
+  }
+  if (options.interactiveOnly) nodes = filterInteractiveSnapshotNodes(nodes);
+  if (typeof options.depth === 'number') nodes = filterSnapshotNodesByDepth(nodes, options.depth);
+  return { ...data, nodes };
+}
+
+export function scopeSnapshotNodes(
+  nodes: RawSnapshotNode[],
+  scope: string,
+  subtreeContributes?: (range: { start: number; end: number }) => boolean,
+): RawSnapshotNode[] {
+  const normalizedScope = normalizeSnapshotScope(scope);
+  if (!normalizedScope) return reindexSnapshotNodes(nodes);
+  const range = findSnapshotScopeRange(nodes, normalizedScope, subtreeContributes);
+  if (!range) return [];
+  const slice = nodes.slice(range.start, range.end);
+  return reindexSnapshotNodes(slice, slice[0]?.depth ?? 0);
+}
+
+function filterInteractiveSnapshotNodes(nodes: RawSnapshotNode[]): RawSnapshotNode[] {
+  if (nodes.length === 0) return nodes;
+  const byIndex = new Map(nodes.map((node) => [node.index, node]));
+  const keepIndexes = new Set<number>();
+  for (const node of nodes) {
+    if (!isInteractiveSnapshotNode(node)) continue;
+    let current: RawSnapshotNode | undefined = node;
+    while (current) {
+      if (keepIndexes.has(current.index)) break;
+      keepIndexes.add(current.index);
+      current =
+        typeof current.parentIndex === 'number' ? byIndex.get(current.parentIndex) : undefined;
+    }
+  }
+  if (keepIndexes.size === 0) return nodes;
+  return reindexSnapshotNodes(nodes.filter((node) => keepIndexes.has(node.index)));
+}
+
+function filterSnapshotNodesByDepth(nodes: RawSnapshotNode[], maxDepth: number): RawSnapshotNode[] {
+  return reindexSnapshotNodes(nodes.filter((node) => (node.depth ?? 0) <= maxDepth));
+}
+
+function isInteractiveSnapshotNode(node: RawSnapshotNode): boolean {
+  if ([node.focused, node.hittable, node.rect].some(Boolean)) return true;
+  const role = `${node.type ?? ''} ${node.role ?? ''} ${node.subrole ?? ''}`.toLowerCase();
+  return INTERACTIVE_ROLE_TOKENS.some((token) => role.includes(token));
+}
diff --git a/packages/contracts/package.json b/packages/contracts/package.json
index 5df12899f..8513fa9e6 100644
--- a/packages/contracts/package.json
+++ b/packages/contracts/package.json
@@ -127,6 +127,10 @@
       "types": "./src/back-runtime.ts",
       "default": "./src/back-runtime.ts"
     },
+    "./backend-diagnostics": {
+      "types": "./src/backend-diagnostics.ts",
+      "default": "./src/backend-diagnostics.ts"
+    },
     "./boot-failure": {
       "types": "./src/boot-failure.ts",
       "default": "./src/boot-failure.ts"
@@ -423,6 +427,10 @@
       "types": "./src/snapshot-runtime.ts",
       "default": "./src/snapshot-runtime.ts"
     },
+    "./snapshot-scope": {
+      "types": "./src/snapshot-scope.ts",
+      "default": "./src/snapshot-scope.ts"
+    },
     "./snapshot-timeout-evidence": {
       "types": "./src/snapshot-timeout-evidence.ts",
       "default": "./src/snapshot-timeout-evidence.ts"
diff --git a/packages/contracts/src/backend-diagnostics.ts b/packages/contracts/src/backend-diagnostics.ts
new file mode 100644
index 000000000..4225c9f51
--- /dev/null
+++ b/packages/contracts/src/backend-diagnostics.ts
@@ -0,0 +1,39 @@
+import type { NetworkIncludeMode } from '@agent-device/kernel/contracts';
+
+export type BackendDiagnosticsTimeWindow = {
+  since?: string;
+  until?: string;
+};
+
+export type BackendDiagnosticsPageOptions = BackendDiagnosticsTimeWindow & {
+  cursor?: string;
+  limit?: number;
+};
+
+export type BackendNetworkIncludeMode = NetworkIncludeMode;
+
+export type BackendNetworkEntry = {
+  timestamp?: string;
+  method?: string;
+  url?: string;
+  status?: number;
+  durationMs?: number;
+  requestHeaders?: Record<string, string>;
+  responseHeaders?: Record<string, string>;
+  requestBody?: string;
+  responseBody?: string;
+  metadata?: Record<string, unknown>;
+};
+
+export type BackendDumpNetworkOptions = BackendDiagnosticsPageOptions & {
+  include?: BackendNetworkIncludeMode;
+};
+
+export type BackendDumpNetworkResult = {
+  entries: readonly BackendNetworkEntry[];
+  nextCursor?: string;
+  timeWindow?: BackendDiagnosticsTimeWindow;
+  backend?: string;
+  redacted?: boolean;
+  notes?: readonly string[];
+};
diff --git a/packages/platform-android/src/app-state.ts b/packages/platform-android/src/app-state.ts
index ae01ce33d..8fb7de478 100644
--- a/packages/platform-android/src/app-state.ts
+++ b/packages/platform-android/src/app-state.ts
@@ -28,6 +28,34 @@ const ANDROID_FOCUS_MARKERS = [
   'ResumedActivity:',
 ] as const;
 
+export type AndroidCommandExecutor = (
+  args: string[],
+  options: { allowFailure: boolean },
+) => Promise<{ exitCode: number; stdout?: string; stderr?: string }>;
+
+export async function readAndroidAppStateWithExecutor(
+  run: AndroidCommandExecutor,
+): Promise<AppStateRuntimeResult> {
+  const windowFocus = await readAndroidFocusWithExecutor(run, FOCUS_COMMANDS);
+  if (windowFocus) return windowFocus;
+
+  const activityFocus = await readAndroidFocusWithExecutor(run, ACTIVITY_COMMANDS);
+  if (activityFocus) return activityFocus;
+  return {};
+}
+
+async function readAndroidFocusWithExecutor(
+  run: AndroidCommandExecutor,
+  commands: readonly (readonly string[])[],
+): Promise<AppStateRuntimeResult | null> {
+  for (const args of commands) {
+    const result = await run([...args], { allowFailure: true });
+    const parsed = parseAndroidForegroundApp(result.stdout ?? '');
+    if (parsed) return parsed;
+  }
+  return null;
+}
+
 export async function readAndroidAppState(
   host: AndroidAppStateHost,
   device: DeviceInfo,
diff --git a/packages/platform-android/src/index.ts b/packages/platform-android/src/index.ts
index 8dbee8bd0..1ca8a52e1 100644
--- a/packages/platform-android/src/index.ts
+++ b/packages/platform-android/src/index.ts
@@ -55,11 +55,11 @@ export async function readAndroidAppState(
   return await read(host, device, signal);
 }
 
-export async function parseAndroidForegroundApp(
-  text: string,
-): Promise<Readonly<{ package?: string; activity?: string }> | null> {
-  const { parseAndroidForegroundApp: parse } = await import('./app-state.ts');
-  return parse(text);
+export async function readAndroidAppStateWithExecutor(
+  run: import('./app-state.ts').AndroidCommandExecutor,
+): Promise<import('@agent-device/contracts/app-state-runtime').AppStateRuntimeResult> {
+  const { readAndroidAppStateWithExecutor: read } = await import('./app-state.ts');
+  return await read(run);
 }
 
 export const runtimeModule = Object.freeze({
diff --git a/scripts/layering/package-boundaries.test.ts b/scripts/layering/package-boundaries.test.ts
index 42037013e..9d7a153fc 100644
--- a/scripts/layering/package-boundaries.test.ts
+++ b/scripts/layering/package-boundaries.test.ts
@@ -75,6 +75,7 @@ const CONTRACT_EXPORTS = [
   '@agent-device/contracts/audio-probe-support',
   '@agent-device/contracts/audio-runtime-plan',
   '@agent-device/contracts/back-mode',
+  '@agent-device/contracts/backend-diagnostics',
   '@agent-device/contracts/back-runtime',
   '@agent-device/contracts/boot-failure',
   '@agent-device/contracts/capture',
@@ -150,6 +151,7 @@ const CONTRACT_EXPORTS = [
   '@agent-device/contracts/snapshot',
   '@agent-device/contracts/snapshot-presentation',
   '@agent-device/contracts/snapshot-runtime',
+  '@agent-device/contracts/snapshot-scope',
   '@agent-device/contracts/snapshot-timeout-evidence',
   '@agent-device/contracts/startup-recovery-fence',
   '@agent-device/contracts/touch-runtime',
@@ -463,6 +465,7 @@ test('the real tree parses, declares, and passes R11', () => {
     '@agent-device/capture-kit/png-worker-client',
     '@agent-device/capture-kit/screenshot-density',
     '@agent-device/capture-kit/screenshot-diff-pixels',
+    '@agent-device/capture-kit/snapshot-desktop-projection',
     '@agent-device/capture-kit/snapshot-occlusion',
     '@agent-device/capture-kit/snapshot-quality-backend-capabilities',
     '@agent-device/capture-kit/snapshot-quality-verdict',
diff --git a/src/__tests__/eager-closure-budgets.ts b/src/__tests__/eager-closure-budgets.ts
index a8cc04988..e4fb35036 100644
--- a/src/__tests__/eager-closure-budgets.ts
+++ b/src/__tests__/eager-closure-budgets.ts
@@ -130,6 +130,7 @@ export const FACADE_BUDGETS: Readonly<Record<string, number>> = Object.freeze({
   'packages/capture-kit/src/screenshot-density.ts': 6,
   'packages/capture-kit/src/screenshot-diff-pixels.ts': 1,
   'packages/capture-kit/src/mobile-snapshot-semantics.ts': 10,
+  'packages/capture-kit/src/snapshot-desktop-projection.ts': 2,
   'packages/capture-kit/src/snapshot-occlusion.ts': 10,
   'packages/capture-kit/src/snapshot-quality-backend-capabilities.ts': 1,
   'packages/capture-kit/src/snapshot-quality-verdict.ts': 2,
@@ -172,6 +173,7 @@ export const FACADE_BUDGETS: Readonly<Record<string, number>> = Object.freeze({
   'packages/contracts/src/audio-probe-support.ts': 5,
   'packages/contracts/src/audio-runtime-plan.ts': 5,
   'packages/contracts/src/back-mode.ts': 1,
+  'packages/contracts/src/backend-diagnostics.ts': 1,
   'packages/contracts/src/boot-failure.ts': 1,
   'packages/contracts/src/click-button.ts': 3,
   'packages/contracts/src/clipboard.ts': 1,
@@ -239,6 +241,7 @@ export const FACADE_BUDGETS: Readonly<Record<string, number>> = Object.freeze({
   'packages/contracts/src/settings.ts': 3,
   'packages/contracts/src/snapshot-presentation.ts': 2,
   'packages/contracts/src/snapshot-runtime.ts': 3,
+  'packages/contracts/src/snapshot-scope.ts': 1,
   'packages/contracts/src/snapshot-timeout-evidence.ts': 1,
   'packages/contracts/src/startup-recovery-fence.ts': 1,
   'packages/contracts/src/tv-remote.ts': 3,
diff --git a/src/backend.ts b/src/backend.ts
index 488fbfcf4..51cedac41 100644
--- a/src/backend.ts
+++ b/src/backend.ts
@@ -15,7 +15,6 @@ import type { ResolvedScrollExecutionOptions } from '@agent-device/contracts/scr
 import type { TvRemoteButton } from '@agent-device/contracts/tv-remote';
 import type { RecordingExportQuality } from '@agent-device/contracts/recording';
 import type { SessionSurface } from '@agent-device/contracts/session';
-import type { NetworkIncludeMode } from '@agent-device/kernel/contracts';
 import type {
   DeviceTarget,
   Platform,
@@ -307,14 +306,22 @@ export type BackendTraceResult = Record<string, unknown> & {
   outPath?: string;
 };
 
-export type BackendDiagnosticsTimeWindow = {
-  since?: string;
-  until?: string;
-};
-
-export type BackendDiagnosticsPageOptions = BackendDiagnosticsTimeWindow & {
-  cursor?: string;
-  limit?: number;
+import type {
+  BackendDiagnosticsPageOptions,
+  BackendDiagnosticsTimeWindow,
+  BackendDumpNetworkOptions,
+  BackendDumpNetworkResult,
+  BackendNetworkEntry,
+  BackendNetworkIncludeMode,
+} from '@agent-device/contracts/backend-diagnostics';
+
+export type {
+  BackendDiagnosticsPageOptions,
+  BackendDiagnosticsTimeWindow,
+  BackendDumpNetworkOptions,
+  BackendDumpNetworkResult,
+  BackendNetworkEntry,
+  BackendNetworkIncludeMode,
 };
 
 export type BackendLogEntry = {
@@ -340,34 +347,6 @@ export type BackendReadLogsResult = {
   notes?: readonly string[];
 };
 
-export type BackendNetworkIncludeMode = NetworkIncludeMode;
-
-export type BackendNetworkEntry = {
-  timestamp?: string;
-  method?: string;
-  url?: string;
-  status?: number;
-  durationMs?: number;
-  requestHeaders?: Record<string, string>;
-  responseHeaders?: Record<string, string>;
-  requestBody?: string;
-  responseBody?: string;
-  metadata?: Record<string, unknown>;
-};
-
-export type BackendDumpNetworkOptions = BackendDiagnosticsPageOptions & {
-  include?: BackendNetworkIncludeMode;
-};
-
-export type BackendDumpNetworkResult = {
-  entries: readonly BackendNetworkEntry[];
-  nextCursor?: string;
-  timeWindow?: BackendDiagnosticsTimeWindow;
-  backend?: string;
-  redacted?: boolean;
-  notes?: readonly string[];
-};
-
 export type BackendPerfMetric = {
   name: string;
   value?: number;
diff --git a/src/core/interactors/linux.ts b/src/core/interactors/linux.ts
index cd8eac4fa..6635740c6 100644
--- a/src/core/interactors/linux.ts
+++ b/src/core/interactors/linux.ts
@@ -21,7 +21,7 @@ import {
 } from '../../platforms/linux/input-actions.ts';
 import { singlePointerPlanEndpoints } from '@agent-device/contracts/gesture-plan';
 import { screenshotLinux } from '../../platforms/linux/screenshot.ts';
-import { captureLinuxSurfaceSnapshot } from '../../snapshot/snapshot-desktop-surface.ts';
+import { captureLinuxSurfaceSnapshot } from '../../platforms/linux/surface-snapshot.ts';
 import type { Interactor } from '@agent-device/contracts/interactor-types';
 
 function unsupportedLinuxAlert(): Promise<never> {
diff --git a/src/core/snapshot-state.ts b/src/core/snapshot-state.ts
index b90f78fcf..5e9a0b83d 100644
--- a/src/core/snapshot-state.ts
+++ b/src/core/snapshot-state.ts
@@ -19,7 +19,7 @@ import {
   annotateSnapshotNodesCoveredByPolicy,
 } from '@agent-device/capture-kit/snapshot-occlusion';
 import { coveredAndroidReplacementNodeIndexes } from '../snapshot/android-replacement-surface-occlusion.ts';
-import { scopeSnapshotNodes } from '../snapshot/snapshot-desktop-surface.ts';
+import { scopeSnapshotNodes } from '@agent-device/capture-kit/snapshot-desktop-projection';
 import { normalizeSnapshotTree, pruneGroupNodes } from '../core/snapshot-tree-ingestion.ts';
 import { presentIosInteractiveSnapshot } from '../snapshot/snapshot-presentation/ios/index.ts';
 
diff --git a/src/platform-runtime.ts b/src/platform-runtime.ts
index fdfe090c3..ae0ea7d73 100644
--- a/src/platform-runtime.ts
+++ b/src/platform-runtime.ts
@@ -31,7 +31,7 @@ import {
 import {
   createAndroidObservationAdapter as createPackageAndroidObservationAdapter,
   createAndroidInventoryModule,
-  parseAndroidForegroundApp as parseAndroidPackageForegroundApp,
+  readAndroidAppStateWithExecutor,
   readAndroidAppState as readAndroidPackageAppState,
   loadShutdownRuntime as loadAndroidShutdownRuntime,
   runtimeModule as androidRuntimeModule,
@@ -74,10 +74,10 @@ export async function readAndroidAppStateWithHost(
   return await readAndroidPackageAppState(host, device, signal);
 }
 
-export async function parseAndroidForegroundApp(
-  text: string,
-): Promise<Readonly<{ package?: string; activity?: string }> | null> {
-  return await parseAndroidPackageForegroundApp(text);
+export async function getAndroidAppStateWithAdb(
+  adb: Parameters<typeof readAndroidAppStateWithExecutor>[0],
+): Promise<AppStateRuntimeResult> {
+  return await readAndroidAppStateWithExecutor(adb);
 }
 
 const androidInventoryModule = createAndroidInventoryModule({
diff --git a/src/platforms/android/__tests__/app-helpers.test.ts b/src/platforms/android/__tests__/app-helpers.test.ts
index 7aa09bda2..54480210a 100644
--- a/src/platforms/android/__tests__/app-helpers.test.ts
+++ b/src/platforms/android/__tests__/app-helpers.test.ts
@@ -4,7 +4,7 @@ import path from 'node:path';
 import { test } from 'vitest';
 import type { AndroidAdbExecutor } from '../adb-executor.ts';
 import { createDeviceAdbExecutor } from '../adb-executor.ts';
-import { getAndroidAppStateWithAdb, listAndroidAppsWithAdb } from '../app-helpers.ts';
+import { listAndroidAppsWithAdb } from '../app-helpers.ts';
 import { mkdtempForTest } from '../../../__tests__/test-utils/tmp-dir.ts';
 
 async function withMockedAdbScript(script: string, run: () => Promise<void>): Promise<void> {
@@ -92,30 +92,9 @@ test('Android app helpers work with a local ADB provider', async () => {
         booted: true,
       });
 
-      const [apps, state] = await Promise.all([
-        listAndroidAppsWithAdb(adb, { target: 'mobile' }),
-        getAndroidAppStateWithAdb(adb),
-      ]);
+      const apps = await listAndroidAppsWithAdb(adb, { target: 'mobile' });
 
       assert.deepEqual(apps, [{ package: 'com.example.app', name: 'Example' }]);
-      assert.deepEqual(state, { package: 'com.example.app', activity: '.MainActivity' });
     },
   );
 });
-
-test('getAndroidAppStateWithAdb parses focus output from failed commands', async () => {
-  const calls: string[][] = [];
-  const adb: AndroidAdbExecutor = async (args) => {
-    calls.push(args);
-    return {
-      exitCode: 1,
-      stdout: 'mCurrentFocus=Window{42 u0 com.example.app/.MainActivity}\n',
-      stderr: 'dumpsys warning',
-    };
-  };
-
-  const state = await getAndroidAppStateWithAdb(adb);
-
-  assert.deepEqual(state, { package: 'com.example.app', activity: '.MainActivity' });
-  assert.deepEqual(calls, [['shell', 'dumpsys', 'window', 'windows']]);
-});
diff --git a/src/platforms/android/app-helpers.ts b/src/platforms/android/app-helpers.ts
index c42f9c513..845bb2056 100644
--- a/src/platforms/android/app-helpers.ts
+++ b/src/platforms/android/app-helpers.ts
@@ -1,5 +1,4 @@
 import { resolveAppsFilter, type AppsFilter } from '@agent-device/contracts/device';
-import type { AppStateRuntimeResult } from '@agent-device/contracts/app-state-runtime';
 import { androidAdbResultError, type AndroidAdbExecutor } from './adb-executor.ts';
 import {
   parseAndroidLaunchablePackages,
@@ -33,23 +32,6 @@ export async function listAndroidAppsWithAdb(
     .sort((a, b) => a.package.localeCompare(b.package));
 }
 
-export async function getAndroidAppStateWithAdb(
-  adb: AndroidAdbExecutor,
-): Promise<AppStateRuntimeResult> {
-  const windowFocus = await readAndroidFocusWithAdb(adb, [
-    ['shell', 'dumpsys', 'window', 'windows'],
-    ['shell', 'dumpsys', 'window'],
-  ]);
-  if (windowFocus) return windowFocus;
-
-  const activityFocus = await readAndroidFocusWithAdb(adb, [
-    ['shell', 'dumpsys', 'activity', 'activities'],
-    ['shell', 'dumpsys', 'activity'],
-  ]);
-  if (activityFocus) return activityFocus;
-  return {};
-}
-
 async function listAndroidLaunchablePackagesWithAdb(
   adb: AndroidAdbExecutor,
   target: AndroidAppListTarget,
@@ -103,16 +85,3 @@ async function listAndroidUserInstalledPackagesWithAdb(adb: AndroidAdbExecutor):
   }
   return parseAndroidUserInstalledPackages(result.stdout);
 }
-
-async function readAndroidFocusWithAdb(
-  adb: AndroidAdbExecutor,
-  commands: string[][],
-): Promise<AppStateRuntimeResult | null> {
-  const { parseAndroidForegroundApp } = await import('../../platform-runtime.ts');
-  for (const args of commands) {
-    const result = await adb(args, { allowFailure: true });
-    const parsed = await parseAndroidForegroundApp(result.stdout ?? '');
-    if (parsed) return parsed;
-  }
-  return null;
-}
diff --git a/src/platforms/apple/interactor.ts b/src/platforms/apple/interactor.ts
index 5e19b22ae..5f9593343 100644
--- a/src/platforms/apple/interactor.ts
+++ b/src/platforms/apple/interactor.ts
@@ -36,7 +36,7 @@ import type {
   SnapshotOptions,
 } from '@agent-device/contracts/interactor-types';
 import { readSnapshotQualityVerdict } from '@agent-device/capture-kit/snapshot-quality-verdict';
-import { captureMacOsSurfaceSnapshot } from '../../snapshot/snapshot-desktop-surface.ts';
+import { captureMacOsSurfaceSnapshot } from './os/macos/surface-snapshot.ts';
 
 export function createAppleInteractor(
   device: DeviceInfo,
diff --git a/src/platforms/apple/os/macos/surface-snapshot.ts b/src/platforms/apple/os/macos/surface-snapshot.ts
new file mode 100644
index 000000000..47d0899eb
--- /dev/null
+++ b/src/platforms/apple/os/macos/surface-snapshot.ts
@@ -0,0 +1,20 @@
+import type { CaptureSnapshotInput } from '@agent-device/contracts/snapshot-runtime';
+import { shapeDesktopSurfaceSnapshot } from '@agent-device/capture-kit/snapshot-desktop-projection';
+
+type SnapshotSurfaceOptions = NonNullable<CaptureSnapshotInput['options']>;
+
+export async function captureMacOsSurfaceSnapshot(
+  options: SnapshotSurfaceOptions,
+  signal?: AbortSignal,
+) {
+  const surface = options.surface;
+  if (!surface || surface === 'app') {
+    throw new TypeError('Apple surface capture requires a non-app macOS surface');
+  }
+  const { runMacOsSnapshotAction } = await import('./helper.ts');
+  const result = await runMacOsSnapshotAction(surface, {
+    bundleId: surface === 'menubar' ? options.appBundleId : undefined,
+    signal,
+  });
+  return shapeDesktopSurfaceSnapshot({ ...result, producer: 'macos-helper' }, options);
+}
diff --git a/src/platforms/linux/surface-snapshot.ts b/src/platforms/linux/surface-snapshot.ts
new file mode 100644
index 000000000..41d9d1d19
--- /dev/null
+++ b/src/platforms/linux/surface-snapshot.ts
@@ -0,0 +1,19 @@
+import type { CaptureSnapshotInput } from '@agent-device/contracts/snapshot-runtime';
+import { shapeDesktopSurfaceSnapshot } from '@agent-device/capture-kit/snapshot-desktop-projection';
+
+export async function captureLinuxSurfaceSnapshot(
+  options: CaptureSnapshotInput['options'],
+  signal?: AbortSignal,
+) {
+  const { snapshotLinux } = await import('./snapshot.ts');
+  const result = await snapshotLinux(options?.surface, signal);
+  return shapeDesktopSurfaceSnapshot(
+    {
+      nodes: result.nodes,
+      truncated: result.truncated,
+      backend: 'linux-atspi',
+      producer: 'linux-atspi',
+    },
+    options ?? {},
+  );
+}
diff --git a/src/platforms/web/agent-browser-network.ts b/src/platforms/web/agent-browser-network.ts
index 7991c3d0a..e0257d15f 100644
--- a/src/platforms/web/agent-browser-network.ts
+++ b/src/platforms/web/agent-browser-network.ts
@@ -2,7 +2,7 @@ import type {
   BackendDumpNetworkOptions,
   BackendDumpNetworkResult,
   BackendNetworkEntry,
-} from '../../backend.ts';
+} from '@agent-device/contracts/backend-diagnostics';
 import { stripUndefined } from '@agent-device/kernel/record';
 import { isJsonObject, readNumberProperty, readStringProperty } from './json-utils.ts';
 
diff --git a/src/platforms/web/provider.ts b/src/platforms/web/provider.ts
index 43a1d19f6..1618a5015 100644
--- a/src/platforms/web/provider.ts
+++ b/src/platforms/web/provider.ts
@@ -2,7 +2,10 @@ import type { ScrollDirection } from '@agent-device/contracts/scroll-gesture';
 import type { SessionSurface } from '@agent-device/contracts/session';
 import { createScopedProvider } from '@agent-device/kernel/scoped-provider';
 import type { RawSnapshotNode } from '@agent-device/kernel/snapshot';
-import type { BackendDumpNetworkOptions, BackendDumpNetworkResult } from '../../backend.ts';
+import type {
+  BackendDumpNetworkOptions,
+  BackendDumpNetworkResult,
+} from '@agent-device/contracts/backend-diagnostics';
 import type { AudioProbeResult } from '@agent-device/contracts/audio-probe-result';
 import { createAgentBrowserWebProvider } from './agent-browser-provider.ts';
 
diff --git a/src/sdk/android-adb.test.ts b/src/sdk/android-adb.test.ts
new file mode 100644
index 000000000..503fb155e
--- /dev/null
+++ b/src/sdk/android-adb.test.ts
@@ -0,0 +1,39 @@
+import assert from 'node:assert/strict';
+import { test } from 'vitest';
+import type { AndroidAdbExecutor } from '../platforms/android/adb-executor.ts';
+import { getAndroidAppStateWithAdb } from './android-adb.ts';
+
+test('getAndroidAppStateWithAdb parses focus output from failed commands', async () => {
+  const calls: string[][] = [];
+  const adb: AndroidAdbExecutor = async (args) => {
+    calls.push(args);
+    return {
+      exitCode: 1,
+      stdout: 'mCurrentFocus=Window{42 u0 com.example.app/.MainActivity}\n',
+      stderr: 'dumpsys warning',
+    };
+  };
+
+  const state = await getAndroidAppStateWithAdb(adb);
+
+  assert.deepEqual(state, { package: 'com.example.app', activity: '.MainActivity' });
+  assert.deepEqual(calls, [['shell', 'dumpsys', 'window', 'windows']]);
+});
+
+test('getAndroidAppStateWithAdb falls back to activity focus and settles empty', async () => {
+  const calls: string[][] = [];
+  const adb: AndroidAdbExecutor = async (args) => {
+    calls.push(args);
+    return { exitCode: 0, stdout: '', stderr: '' };
+  };
+
+  const state = await getAndroidAppStateWithAdb(adb);
+
+  assert.deepEqual(state, {});
+  assert.deepEqual(calls, [
+    ['shell', 'dumpsys', 'window', 'windows'],
+    ['shell', 'dumpsys', 'window'],
+    ['shell', 'dumpsys', 'activity', 'activities'],
+    ['shell', 'dumpsys', 'activity'],
+  ]);
+});
diff --git a/src/sdk/android-adb.ts b/src/sdk/android-adb.ts
index 74490b4ca..12a0f87c3 100644
--- a/src/sdk/android-adb.ts
+++ b/src/sdk/android-adb.ts
@@ -5,10 +5,18 @@ export {
   type AndroidAdbProvider,
   type AndroidPortReverseEndpoint,
 } from '../platforms/android/adb-executor.ts';
-export {
-  getAndroidAppStateWithAdb,
-  listAndroidAppsWithAdb,
-} from '../platforms/android/app-helpers.ts';
+export { listAndroidAppsWithAdb } from '../platforms/android/app-helpers.ts';
+
+import type { AndroidAdbExecutor } from '../platforms/android/adb-executor.ts';
+import type { AppStateRuntimeResult } from '@agent-device/contracts/app-state-runtime';
+
+export async function getAndroidAppStateWithAdb(
+  adb: AndroidAdbExecutor,
+): Promise<AppStateRuntimeResult> {
+  const { getAndroidAppStateWithAdb: read } = await import('../platform-runtime.ts');
+  return await read(adb);
+}
+
 export {
   forceStopAndroidAppWithAdb,
   openAndroidAppWithAdb,
diff --git a/src/sdk/limrun-runtime-dependencies.test.ts b/src/sdk/limrun-runtime-dependencies.test.ts
index 4ca6e58eb..d6d8d64a9 100644
--- a/src/sdk/limrun-runtime-dependencies.test.ts
+++ b/src/sdk/limrun-runtime-dependencies.test.ts
@@ -15,10 +15,6 @@ vi.mock('@limrun/api', () => ({
 vi.mock('../platforms/android/app-helpers.ts', () => {
   moduleLoads.androidAppHelpers += 1;
   return {
-    getAndroidAppStateWithAdb: vi.fn(async () => ({
-      package: 'com.example.app',
-      activity: '.MainActivity',
-    })),
     listAndroidAppsWithAdb: vi.fn(async () => [{ package: 'com.example.app', name: 'Example' }]),
   };
 });
diff --git a/src/snapshot/snapshot-desktop-surface.test.ts b/src/snapshot/snapshot-desktop-surface.test.ts
index b8418a370..d80893042 100644
--- a/src/snapshot/snapshot-desktop-surface.test.ts
+++ b/src/snapshot/snapshot-desktop-surface.test.ts
@@ -1,6 +1,4 @@
 import { beforeEach, expect, test, vi } from 'vitest';
-import fs from 'node:fs';
-import path from 'node:path';
 import type { DeviceInfo } from '@agent-device/kernel/device';
 
 const { runMacOsSnapshotAction, snapshotLinux } = vi.hoisted(() => ({
@@ -11,7 +9,7 @@ const { runMacOsSnapshotAction, snapshotLinux } = vi.hoisted(() => ({
 vi.mock('../platforms/apple/os/macos/helper.ts', () => ({ runMacOsSnapshotAction }));
 vi.mock('../platforms/linux/snapshot.ts', () => ({ snapshotLinux }));
 
-import { createSnapshotRuntimeHost, scopeSnapshotNodes } from './snapshot-desktop-surface.ts';
+import { createSnapshotRuntimeHost } from './snapshot-desktop-surface.ts';
 
 const macosDevice = {
   id: 'desktop',
@@ -94,45 +92,3 @@ test('Linux snapshot host preserves interactive ancestor projection before depth
     ],
   });
 });
-
-// Golden scope-policy leg (#1832 C2): the post-wire pass must agree with
-// contracts/fixtures/snapshot-scope-policy.json — the same table the Android projection and the
-// shared predicate are asserted against. Fixture position rides in `rect.x` so the check is
-// text-independent.
-test('scopeSnapshotNodes agrees with every golden scope-policy table case', () => {
-  const cases = JSON.parse(
-    fs.readFileSync(
-      path.resolve(import.meta.dirname, '../../contracts/fixtures/snapshot-scope-policy.json'),
-      'utf8',
-    ),
-  ) as Array<{
-    name: string;
-    scope: string;
-    nodes: Array<{
-      depth: number;
-      label?: string;
-      value?: string;
-      identifier?: string;
-      presented?: boolean;
-    }>;
-    expectedSubtreeIndexes: number[];
-  }>;
-  expect(cases.length).toBeGreaterThan(0);
-  for (const fixture of cases) {
-    const parents: number[] = [];
-    const nodes = fixture.nodes.map((node, index) => {
-      parents.length = node.depth;
-      const parentIndex = node.depth > 0 ? parents[node.depth - 1] : undefined;
-      parents[node.depth] = index;
-      return { ...node, index, parentIndex, rect: { x: index, y: 0, width: 1, height: 1 } };
-    });
-    const scoped = scopeSnapshotNodes(nodes, fixture.scope, (range) =>
-      nodes.slice(range.start, range.end).some((node) => node.presented !== false),
-    );
-    expect(
-      scoped.map((node) => node.rect?.x),
-      fixture.name,
-    ).toEqual(fixture.expectedSubtreeIndexes);
-    if (scoped.length > 0) expect(scoped[0]?.depth, fixture.name).toBe(0);
-  }
-});
diff --git a/src/snapshot/snapshot-desktop-surface.ts b/src/snapshot/snapshot-desktop-surface.ts
index 57628d1d7..7d1cc6b16 100644
--- a/src/snapshot/snapshot-desktop-surface.ts
+++ b/src/snapshot/snapshot-desktop-surface.ts
@@ -1,60 +1,18 @@
-import type { RawSnapshotNode } from '@agent-device/kernel/snapshot';
-import type { SnapshotOptions, SnapshotResult } from '@agent-device/contracts/interactor-types';
-import type {
-  CaptureSnapshotInput,
-  SnapshotRuntimeHost,
-} from '@agent-device/contracts/snapshot-runtime';
+import type { SnapshotRuntimeHost } from '@agent-device/contracts/snapshot-runtime';
 import type { DeviceInfo } from '@agent-device/kernel/device';
-import {
-  findSnapshotScopeRange,
-  normalizeSnapshotScope,
-  reindexSnapshotNodes,
-} from '@agent-device/contracts/snapshot';
-
-type SnapshotSurfaceOptions = NonNullable<CaptureSnapshotInput['options']>;
 
 export function createSnapshotRuntimeHost(): SnapshotRuntimeHost {
   return Object.freeze({ captureSurface });
 }
 
-export async function captureLinuxSurfaceSnapshot(
-  options: CaptureSnapshotInput['options'],
-  signal?: AbortSignal,
-) {
-  const { snapshotLinux } = await import('../platforms/linux/snapshot.ts');
-  const result = await snapshotLinux(options?.surface, signal);
-  return shapeDesktopSurfaceSnapshot(
-    {
-      nodes: result.nodes,
-      truncated: result.truncated,
-      backend: 'linux-atspi',
-      producer: 'linux-atspi',
-    },
-    options ?? {},
-  );
-}
-
-export async function captureMacOsSurfaceSnapshot(
-  options: SnapshotSurfaceOptions,
-  signal?: AbortSignal,
-) {
-  const surface = options.surface;
-  if (!surface || surface === 'app') {
-    throw new TypeError('Apple surface capture requires a non-app macOS surface');
-  }
-  const { runMacOsSnapshotAction } = await import('../platforms/apple/os/macos/helper.ts');
-  const result = await runMacOsSnapshotAction(surface, {
-    bundleId: surface === 'menubar' ? options.appBundleId : undefined,
-    signal,
-  });
-  return shapeDesktopSurfaceSnapshot({ ...result, producer: 'macos-helper' }, options);
-}
-
 const captureSurface: SnapshotRuntimeHost['captureSurface'] = async (device, options, signal) => {
   if (device.platform === 'linux') {
+    const { captureLinuxSurfaceSnapshot } = await import('../platforms/linux/surface-snapshot.ts');
     return await captureLinuxSurfaceSnapshot(options, signal);
   }
   requireMacOsSurfaceDevice(device);
+  const { captureMacOsSurfaceSnapshot } =
+    await import('../platforms/apple/os/macos/surface-snapshot.ts');
   return await captureMacOsSurfaceSnapshot(options ?? {}, signal);
 };
 
@@ -63,73 +21,3 @@ function requireMacOsSurfaceDevice(device: DeviceInfo): void {
     throw new TypeError('Apple surface capture requires a non-app macOS surface');
   }
 }
-
-const INTERACTIVE_ROLE_TOKENS = [
-  'button',
-  'menu',
-  'textfield',
-  'searchfield',
-  'checkbox',
-  'radio',
-  'switch',
-] as const;
-
-/** Applies the legacy desktop-surface projection once for both runtime hosts and legacy capture. */
-function shapeDesktopSurfaceSnapshot(
-  data: SnapshotResult,
-  options: Pick<SnapshotOptions, 'depth' | 'interactiveOnly' | 'scope'>,
-): SnapshotResult {
-  let nodes = data.nodes ?? [];
-  if (options.scope) {
-    nodes = scopeSnapshotNodes(nodes, options.scope, (range) =>
-      options.interactiveOnly
-        ? nodes.slice(range.start, range.end).some(isInteractiveSnapshotNode)
-        : true,
-    );
-  }
-  if (options.interactiveOnly) nodes = filterInteractiveSnapshotNodes(nodes);
-  if (typeof options.depth === 'number') nodes = filterSnapshotNodesByDepth(nodes, options.depth);
-  return { ...data, nodes };
-}
-
-/** The shared scope specification applied post-wire (`@agent-device/contracts/snapshot`). */
-export function scopeSnapshotNodes(
-  nodes: RawSnapshotNode[],
-  scope: string,
-  subtreeContributes?: (range: { start: number; end: number }) => boolean,
-): RawSnapshotNode[] {
-  const normalizedScope = normalizeSnapshotScope(scope);
-  if (!normalizedScope) return reindexSnapshotNodes(nodes);
-  const range = findSnapshotScopeRange(nodes, normalizedScope, subtreeContributes);
-  if (!range) return [];
-  const slice = nodes.slice(range.start, range.end);
-  return reindexSnapshotNodes(slice, slice[0]?.depth ?? 0);
-}
-
-function filterInteractiveSnapshotNodes(nodes: RawSnapshotNode[]): RawSnapshotNode[] {
-  if (nodes.length === 0) return nodes;
-  const byIndex = new Map(nodes.map((node) => [node.index, node]));
-  const keepIndexes = new Set<number>();
-  for (const node of nodes) {
-    if (!isInteractiveSnapshotNode(node)) continue;
-    let current: RawSnapshotNode | undefined = node;
-    while (current) {
-      if (keepIndexes.has(current.index)) break;
-      keepIndexes.add(current.index);
-      current =
-        typeof current.parentIndex === 'number' ? byIndex.get(current.parentIndex) : undefined;
-    }
-  }
-  if (keepIndexes.size === 0) return nodes;
-  return reindexSnapshotNodes(nodes.filter((node) => keepIndexes.has(node.index)));
-}
-
-function filterSnapshotNodesByDepth(nodes: RawSnapshotNode[], maxDepth: number): RawSnapshotNode[] {
-  return reindexSnapshotNodes(nodes.filter((node) => (node.depth ?? 0) <= maxDepth));
-}
-
-function isInteractiveSnapshotNode(node: RawSnapshotNode): boolean {
-  if ([node.focused, node.hittable, node.rect].some(Boolean)) return true;
-  const role = `${node.type ?? ''} ${node.role ?? ''} ${node.subrole ?? ''}`.toLowerCase();
-  return INTERACTIVE_ROLE_TOKENS.some((token) => role.includes(token));
-}