diff --git a/lib/notmuch.h b/lib/notmuch.h
index 0d9cb0f5..88da0789 100644
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -247,8 +247,9 @@ notmuch_database_get_directory (notmuch_database_t *database,
  * NOTMUCH_STATUS_SUCCESS: Message successfully added to database.
  *
  * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: Message has the same message
- *	ID as another message already in the database. The new filename
- *	was successfully added to the message in the database.
+ *	ID as another message already in the database. The new
+ *	filename was successfully added to the message in the database
+ *	(if not already present).
  *
  * NOTMUCH_STATUS_FILE_ERROR: an error occurred trying to open the
  *	file, (such as permission denied, or file not found,