@@ -18,15 +18,14 @@ export type AndroidGestureViewportReading = Readonly<{
 }>;
 
 export function validateAndroidGestureViewport(viewport: Rect): Rect {
-  if (!isMeasurableRect(viewport))
+  if (
+    !Number.isFinite(viewport.x) ||
+    !Number.isFinite(viewport.y) ||
+    !Number.isFinite(viewport.width) ||
+    !Number.isFinite(viewport.height) ||
+    viewport.width <= 0 ||
+    viewport.height <= 0
+  )
     throw new AppError('COMMAND_FAILED', 'Android helper returned an invalid gesture viewport');
   return viewport;
 }
-
-export function isMeasurableRect(rect: Rect): boolean {
-  return (
-    [rect.x, rect.y, rect.width, rect.height].every((value) => Number.isFinite(value)) &&
-    rect.width > 0 &&
-    rect.height > 0
-  );
-}
@@ -251,7 +251,8 @@ function resolveAndroidScrollSurface(
   const clip = clipScrollViewportAboveKeyboard(viewport, keyboard);
   if (clip.kind === 'occluded') {
     throw scrollKeyboardOccludesSurfaceError(direction, {
-      ...clip,
+      keyboardMinY: clip.keyboardMinY,
+      visibleHeight: clip.visibleHeight,
       viewportHeight: viewport.height,
     });
   }
 
@@ -15,7 +15,6 @@ import {
   readInstrumentationResultNumber,
 } from './instrumentation-helper.ts';
 import {
-  isMeasurableRect,
   validateAndroidGestureViewport,
   type AndroidGestureViewportReading,
 } from './gesture-viewport.ts';
@@ -348,7 +347,11 @@ function readViewportResult(record: Record<string, string>): AndroidGestureViewp
   };
 }
 
-/** Absence of any keyboard key is the helper's way of saying no input method window is on screen. */
+/**
+ * Absence of any keyboard key is the helper's way of saying no input method window is on screen.
+ * The frame is not validated here: the shared clip rule fails open on one it cannot measure, and a
+ * helper that cannot size the IME must not fail every scroll.
+ */
 function readKeyboardResult(record: Record<string, string>): Rect | undefined {
   const x = readInstrumentationResultNumber(record.keyboardX);
   const y = readInstrumentationResultNumber(record.keyboardY);
@@ -357,8 +360,5 @@ function readKeyboardResult(record: Record<string, string>): Rect | undefined {
   if (x === undefined || y === undefined || width === undefined || height === undefined) {
     return undefined;
   }
-  // An IME window the helper cannot size is dropped, not refused: the clip rule already fails open
-  // on a missing frame, and a helper that cannot see it must not fail every scroll.
-  const keyboard = { x, y, width, height };
-  return isMeasurableRect(keyboard) ? keyboard : undefined;
+  return { x, y, width, height };
 }