diff --git a/youtube_dl/extractor/common.py b/youtube_dl/extractor/common.py
index d5faa0eb749..0b9a5359ec8 100644
--- a/youtube_dl/extractor/common.py
+++ b/youtube_dl/extractor/common.py
@@ -287,6 +287,8 @@ class InfoExtractor(object):
                         * "start_time" - The start time of the chapter in seconds
                         * "end_time" - The end time of the chapter in seconds
                         * "title" (optional, string)
+    playable_in_embed: True, False, or None (=unknown). Whether this video is
+                    allowed to play in embedded players on other sites
 
     The following fields should only be used when the video belongs to some logical
     chapter or section: