Define the type of the power_level_content_override field

api/client-server/create_room.yaml

@@ -198,6 +198,7 @@ paths:
                   ``invite_3pid``. See `Direct Messaging`_ for more information.
               power_level_content_override:
                 title: Power Level Event Content
+                type: object
                 description: |-
                   The power level content to override in the default power level
                   event. This object is applied on top of the generated `m.room.power_levels`_