diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/ISplitScreen.aidl b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/ISplitScreen.aidl
index ecdafa9..03688b7 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/ISplitScreen.aidl
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/ISplitScreen.aidl
@@ -79,23 +79,23 @@
     /**
      * Starts tasks simultaneously in one transition.
      */
-    oneway void startTasks(int mainTaskId, in Bundle mainOptions, int sideTaskId,
-            in Bundle sideOptions, int sidePosition, float splitRatio,
-            in RemoteTransition remoteTransition, in InstanceId instanceId) = 10;
+    oneway void startTasks(int taskId1, in Bundle options1, int taskId2, in Bundle options2,
+            int splitPosition, float splitRatio, in RemoteTransition remoteTransition,
+            in InstanceId instanceId) = 10;
 
     /**
      * Version of startTasks using legacy transition system.
      */
-    oneway void startTasksWithLegacyTransition(int mainTaskId, in Bundle mainOptions,
-            int sideTaskId, in Bundle sideOptions, int sidePosition,
-            float splitRatio, in RemoteAnimationAdapter adapter, in InstanceId instanceId) = 11;
+    oneway void startTasksWithLegacyTransition(int taskId1, in Bundle options1, int taskId2,
+            in Bundle options2, int splitPosition, float splitRatio,
+            in RemoteAnimationAdapter adapter, in InstanceId instanceId) = 11;
 
     /**
      * Starts a pair of intent and task using legacy transition system.
      */
     oneway void startIntentAndTaskWithLegacyTransition(in PendingIntent pendingIntent,
-            in Intent fillInIntent, int taskId, in Bundle mainOptions,in Bundle sideOptions,
-            int sidePosition, float splitRatio, in RemoteAnimationAdapter adapter,
+            in Intent fillInIntent, in Bundle options1, int taskId, in Bundle options2,
+            int splitPosition, float splitRatio, in RemoteAnimationAdapter adapter,
             in InstanceId instanceId) = 12;
 
     /**
@@ -115,7 +115,7 @@
     /**
      * Starts a pair of shortcut and task using legacy transition system.
      */
-    oneway void startShortcutAndTaskWithLegacyTransition(in ShortcutInfo shortcutInfo, int taskId,
-            in Bundle mainOptions, in Bundle sideOptions, int sidePosition, float splitRatio,
+    oneway void startShortcutAndTaskWithLegacyTransition(in ShortcutInfo shortcutInfo,
+            in Bundle options1, int taskId, in Bundle options2, int splitPosition, float splitRatio,
             in RemoteAnimationAdapter adapter, in InstanceId instanceId) = 15;
 }
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/SplitScreenController.java b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/SplitScreenController.java
index 07a6895..8043b97 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/SplitScreenController.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/SplitScreenController.java
@@ -828,47 +828,46 @@
         }
 
         @Override
-        public void startTasksWithLegacyTransition(int mainTaskId, @Nullable Bundle mainOptions,
-                int sideTaskId, @Nullable Bundle sideOptions, @SplitPosition int sidePosition,
+        public void startTasksWithLegacyTransition(int taskId1, @Nullable Bundle options1,
+                int taskId2, @Nullable Bundle options2, @SplitPosition int splitPosition,
                 float splitRatio, RemoteAnimationAdapter adapter, InstanceId instanceId) {
             executeRemoteCallWithTaskPermission(mController, "startTasks",
                     (controller) -> controller.mStageCoordinator.startTasksWithLegacyTransition(
-                            mainTaskId, mainOptions, sideTaskId, sideOptions, sidePosition,
+                            taskId1, options1, taskId2, options2, splitPosition,
                             splitRatio, adapter, instanceId));
         }
 
         @Override
         public void startIntentAndTaskWithLegacyTransition(PendingIntent pendingIntent,
-                Intent fillInIntent, int taskId, Bundle mainOptions, Bundle sideOptions,
-                int sidePosition, float splitRatio, RemoteAnimationAdapter adapter,
+                Intent fillInIntent, Bundle options1, int taskId, Bundle options2,
+                int splitPosition, float splitRatio, RemoteAnimationAdapter adapter,
                 InstanceId instanceId) {
             executeRemoteCallWithTaskPermission(mController,
                     "startIntentAndTaskWithLegacyTransition", (controller) ->
                             controller.mStageCoordinator.startIntentAndTaskWithLegacyTransition(
-                                    pendingIntent, fillInIntent, taskId, mainOptions, sideOptions,
-                                    sidePosition, splitRatio, adapter, instanceId));
+                                    pendingIntent, fillInIntent, options1, taskId, options2,
+                                    splitPosition, splitRatio, adapter, instanceId));
         }
 
         @Override
         public void startShortcutAndTaskWithLegacyTransition(ShortcutInfo shortcutInfo,
-                int taskId, @Nullable Bundle mainOptions, @Nullable Bundle sideOptions,
-                @SplitPosition int sidePosition, float splitRatio, RemoteAnimationAdapter adapter,
+                @Nullable Bundle options1, int taskId, @Nullable Bundle options2,
+                @SplitPosition int splitPosition, float splitRatio, RemoteAnimationAdapter adapter,
                 InstanceId instanceId) {
             executeRemoteCallWithTaskPermission(mController,
                     "startShortcutAndTaskWithLegacyTransition", (controller) ->
                             controller.mStageCoordinator.startShortcutAndTaskWithLegacyTransition(
-                                    shortcutInfo, taskId, mainOptions, sideOptions, sidePosition,
+                                    shortcutInfo, options1, taskId, options2, splitPosition,
                                     splitRatio, adapter, instanceId));
         }
 
         @Override
-        public void startTasks(int mainTaskId, @Nullable Bundle mainOptions,
-                int sideTaskId, @Nullable Bundle sideOptions,
-                @SplitPosition int sidePosition, float splitRatio,
+        public void startTasks(int taskId1, @Nullable Bundle options1, int taskId2,
+                @Nullable Bundle options2, @SplitPosition int splitPosition, float splitRatio,
                 @Nullable RemoteTransition remoteTransition, InstanceId instanceId) {
             executeRemoteCallWithTaskPermission(mController, "startTasks",
-                    (controller) -> controller.mStageCoordinator.startTasks(mainTaskId, mainOptions,
-                            sideTaskId, sideOptions, sidePosition, splitRatio, remoteTransition,
+                    (controller) -> controller.mStageCoordinator.startTasks(taskId1, options1,
+                            taskId2, options2, splitPosition, splitRatio, remoteTransition,
                             instanceId));
         }
 
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
index c17f822..d79e6a1 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java
@@ -516,8 +516,8 @@
     }
 
     /** Starts 2 tasks in one transition. */
-    void startTasks(int mainTaskId, @Nullable Bundle mainOptions, int sideTaskId,
-            @Nullable Bundle sideOptions, @SplitPosition int sidePosition, float splitRatio,
+    void startTasks(int sideTaskId, @Nullable Bundle sideOptions, int mainTaskId,
+            @Nullable Bundle mainOptions, @SplitPosition int sidePosition, float splitRatio,
             @Nullable RemoteTransition remoteTransition, InstanceId instanceId) {
         final WindowContainerTransaction wct = new WindowContainerTransaction();
         mainOptions = mainOptions != null ? mainOptions : new Bundle();
@@ -550,44 +550,45 @@
         setEnterInstanceId(instanceId);
     }
 
-    /** Starts 2 tasks in one legacy transition. */
-    void startTasksWithLegacyTransition(int mainTaskId, @Nullable Bundle mainOptions,
-            int sideTaskId, @Nullable Bundle sideOptions, @SplitPosition int sidePosition,
+    /** Starts a pair of tasks using legacy transition. */
+    void startTasksWithLegacyTransition(int taskId1, @Nullable Bundle options1,
+            int taskId2, @Nullable Bundle options2, @SplitPosition int splitPosition,
             float splitRatio, RemoteAnimationAdapter adapter,
             InstanceId instanceId) {
         final WindowContainerTransaction wct = new WindowContainerTransaction();
-        if (sideOptions == null) sideOptions = new Bundle();
-        addActivityOptions(sideOptions, mSideStage);
-        wct.startTask(sideTaskId, sideOptions);
+        if (options1 == null) options1 = new Bundle();
+        addActivityOptions(options1, mSideStage);
+        wct.startTask(taskId1, options1);
 
-        startWithLegacyTransition(wct, mainTaskId, mainOptions, sidePosition, splitRatio, adapter,
+        startWithLegacyTransition(wct, taskId2, options2, splitPosition, splitRatio, adapter,
                 instanceId);
     }
 
-    /** Start an intent and a task ordered by {@code intentFirst}. */
+    /** Starts a pair of intent and task using legacy transition. */
     void startIntentAndTaskWithLegacyTransition(PendingIntent pendingIntent, Intent fillInIntent,
-            int taskId, @Nullable Bundle mainOptions, @Nullable Bundle sideOptions,
-            @SplitPosition int sidePosition, float splitRatio, RemoteAnimationAdapter adapter,
+            @Nullable Bundle options1, int taskId, @Nullable Bundle options2,
+            @SplitPosition int splitPosition, float splitRatio, RemoteAnimationAdapter adapter,
             InstanceId instanceId) {
         final WindowContainerTransaction wct = new WindowContainerTransaction();
-        if (sideOptions == null) sideOptions = new Bundle();
-        addActivityOptions(sideOptions, mSideStage);
-        wct.sendPendingIntent(pendingIntent, fillInIntent, sideOptions);
+        if (options1 == null) options1 = new Bundle();
+        addActivityOptions(options1, mSideStage);
+        wct.sendPendingIntent(pendingIntent, fillInIntent, options1);
 
-        startWithLegacyTransition(wct, taskId, mainOptions, sidePosition, splitRatio, adapter,
+        startWithLegacyTransition(wct, taskId, options2, splitPosition, splitRatio, adapter,
                 instanceId);
     }
 
+    /** Starts a pair of shortcut and task using legacy transition. */
     void startShortcutAndTaskWithLegacyTransition(ShortcutInfo shortcutInfo,
-            int taskId, @Nullable Bundle mainOptions, @Nullable Bundle sideOptions,
-            @SplitPosition int sidePosition, float splitRatio, RemoteAnimationAdapter adapter,
+            @Nullable Bundle options1, int taskId, @Nullable Bundle options2,
+            @SplitPosition int splitPosition, float splitRatio, RemoteAnimationAdapter adapter,
             InstanceId instanceId) {
         final WindowContainerTransaction wct = new WindowContainerTransaction();
-        if (sideOptions == null) sideOptions = new Bundle();
-        addActivityOptions(sideOptions, mSideStage);
-        wct.startShortcut(mContext.getPackageName(), shortcutInfo, sideOptions);
+        if (options1 == null) options1 = new Bundle();
+        addActivityOptions(options1, mSideStage);
+        wct.startShortcut(mContext.getPackageName(), shortcutInfo, options1);
 
-        startWithLegacyTransition(wct, taskId, mainOptions, sidePosition, splitRatio, adapter,
+        startWithLegacyTransition(wct, taskId, options2, splitPosition, splitRatio, adapter,
                 instanceId);
     }