diff --git a/include/media/AudioSystem.h b/include/media/AudioSystem.h
index 28fdfd4..3faaa7e 100644
--- a/include/media/AudioSystem.h
+++ b/include/media/AudioSystem.h
@@ -141,7 +141,13 @@
     // return the number of input frames lost by HAL implementation, or 0 if the handle is invalid
     static uint32_t getInputFramesLost(audio_io_handle_t ioHandle);
 
+    // Allocate a new audio session ID and return that new ID.
+    // If unable to contact AudioFlinger, returns AUDIO_SESSION_ALLOCATE instead.
+    // FIXME If AudioFlinger were to ever exhaust the session ID namespace,
+    //       this method could fail by returning either AUDIO_SESSION_ALLOCATE
+    //       or an unspecified existing session ID.
     static int newAudioSessionId();
+
     static void acquireAudioSessionId(int audioSession, pid_t pid);
     static void releaseAudioSessionId(int audioSession, pid_t pid);