diff --git a/messages b/messages
index 4dffbfb65..313d0a569 100644
--- a/messages
+++ b/messages
@@ -15,6 +15,7 @@
 #  the message has an identifier, else unused.
 # CHANCE <chance>: optional chance of the message appearing in a book, relative
 #  to the sum of all chances. 0 or no line means this message will never appear.
+# FACE <face's name>: the message's face, for knowledge management. Optional.
 # TEXT: start of the message's body
 # ENDMSG: marks the end of a message's body and message.
 # QUEST: optional quest internal code and state this message will activate.