diff --git a/vibrator/aidl/android/hardware/vibrator/IVibrator.aidl b/vibrator/aidl/android/hardware/vibrator/IVibrator.aidl
index 06a8bf5..6489c1d 100644
--- a/vibrator/aidl/android/hardware/vibrator/IVibrator.aidl
+++ b/vibrator/aidl/android/hardware/vibrator/IVibrator.aidl
@@ -202,6 +202,12 @@
      * once enabled and assigned an effect to play. This may not be supported
      * and this support is reflected in getCapabilities (CAP_ALWAYS_ON_CONTROL).
      *
+     * The always-on source ID is conveyed directly to clients through
+     * device/board configuration files ensuring that no ID is assigned to
+     * multiple clients. No client should use this API unless explicitly
+     * assigned an always-on source ID. Clients must develop their own way to
+     * get IDs from vendor in a stable way.
+     *
      * @param id The device-specific always-on source ID to enable.
      * @param effect The type of haptic event to trigger.
      * @param strength The intensity of haptic event to trigger.
@@ -212,6 +218,12 @@
      * Disable an always-on haptic source. This may not be supported and this
      * support is reflected in getCapabilities (CAP_ALWAYS_ON_CONTROL).
      *
+     * The always-on source ID is conveyed directly to clients through
+     * device/board configuration files ensuring that no ID is assigned to
+     * multiple clients. No client should use this API unless explicitly
+     * assigned an always-on source ID. Clients must develop their own way to
+     * get IDs from vendor in a stable way.
+     *
      * @param id The device-specific always-on source ID to disable.
      */
     void alwaysOnDisable(in int id);