Document TextChannel.start_thread return type

discord/channel.py

@@ -668,6 +668,11 @@ class TextChannel(discord.abc.Messageable, discord.abc.GuildChannel, Hashable):
             You do not have permissions to start a thread.
         HTTPException
             Starting the thread failed.
+
+        Returns
+        --------
+        :class:`Thread`
+            The started thread
         """
 
         if message is None:

discord/message.py

@@ -1475,6 +1475,11 @@ class Message(Hashable):
             Starting the thread failed.
         InvalidArgument
             This message does not have guild info attached.
+
+        Returns
+        --------
+        :class:`.Thread`
+            The started thread.
         """
         if self.guild is None:
             raise InvalidArgument('This message does not have guild info attached.')