diff --git a/src/client/protocols/outputdevice.xml b/src/client/protocols/outputdevice.xml
--- a/src/client/protocols/outputdevice.xml
+++ b/src/client/protocols/outputdevice.xml
@@ -375,6 +375,36 @@
+
+
+
+ This event indicates a change to the output being part of the overall presentation by
+ the compositor as in presenting content.
+
+ A compositor might reposition outputs on such an event to fill the compositor space
+ again without gaps between the outputs and to move the origin relatively.
+
+ There might be different reasons for such an event and the trigger argument provides
+ more information on that:
+
+ * enablement flag is sent when the device is removed from the overall presentation
+ because it was disabled. Note that a compositor might want to keep a disabled output
+ as a space consuming part of the overall compositor space although it is disabled. In
+ this case the event should not be sent.
+ * hotplug flag is sent after the device gets connected or disconnected. As long as no
+ other information is available this flag should be sent after the device was connected
+ and clients are binding for the first time to the device.
+ * dpms flag is sent after the device was turned off via hardware key or through other
+ means changing its DPMS state. When the session in general suspends or shut downs it
+ should the compositor should not send the event since the the session can continue
+ later on in the same overall compositor space state as before.
+
+ The direction argument indicates that the output device is presenting from now on if it
+ is set to the up value and that it is not presenting any longer when set to down.
+
+
+
+