diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 61048f4dcf..aa14431a8f 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -2873,6 +2873,7 @@ typedef struct AVCodecContext {
      * However for formats that do not use pre-multiplied alpha
      * there might be serious artefacts (though e.g. libswscale currently
      * assumes pre-multiplied alpha anyway).
+     * Code outside libavcodec should access this field using AVOptions
      *
      * - decoding: set by user
      * - encoding: unused