diff --git a/mediapipe/tasks/ios/vision/image_classifier/sources/MPPImageClassifierOptions.h b/mediapipe/tasks/ios/vision/image_classifier/sources/MPPImageClassifierOptions.h
index a29de0762..92f8ebc5d 100644
--- a/mediapipe/tasks/ios/vision/image_classifier/sources/MPPImageClassifierOptions.h
+++ b/mediapipe/tasks/ios/vision/image_classifier/sources/MPPImageClassifierOptions.h
@@ -29,11 +29,10 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * The delegate of `MPPImageClassifier` must adopt `MPPImageClassifierDelegate` protocol.
  * The methods in this protocol are optional.
- * TODO: Add parameter `MPPImage` in the callback.
  */
 NS_SWIFT_NAME(ImageClassifierDelegate)
 @protocol MPPImageClassifierDelegate <NSObject>
-@required
+@optional
 - (void)imageClassifier:(MPPImageClassifier *)imageClassifier
     didFinishClassificationWithResult:(nullable MPPImageClassifierResult *)result
               timestampInMilliseconds:(NSInteger)timestampInMilliseconds
diff --git a/mediapipe/tasks/ios/vision/object_detector/sources/MPPObjectDetectorOptions.h b/mediapipe/tasks/ios/vision/object_detector/sources/MPPObjectDetectorOptions.h
index 352ce960c..113a2914f 100644
--- a/mediapipe/tasks/ios/vision/object_detector/sources/MPPObjectDetectorOptions.h
+++ b/mediapipe/tasks/ios/vision/object_detector/sources/MPPObjectDetectorOptions.h
@@ -32,7 +32,7 @@ NS_ASSUME_NONNULL_BEGIN
  * TODO: Add parameter `MPPImage` in the callback.
  */
 @protocol MPPObjectDetectorDelegate <NSObject>
-@required
+@optional
 - (void)objectDetector:(MPPObjectDetector *)objectDetector
     didFinishDetectionWithResult:(nullable MPPObjectDetectionResult *)result
          timestampInMilliseconds:(NSInteger)timestampInMilliseconds