diff --git a/headers/private/app/ServerProtocol.h b/headers/private/app/ServerProtocol.h
index 1690152538..84846e176e 100644
--- a/headers/private/app/ServerProtocol.h
+++ b/headers/private/app/ServerProtocol.h
@@ -104,6 +104,12 @@ AS_FOCUS_FOLLOWS_MOUSE,
 AS_SET_MOUSE_MODE,
 AS_GET_MOUSE_MODE,
 
+// Hook function messages
+AS_WORKSPACE_ACTIVATED,
+AS_WORKSPACES_CHANGED,
+AS_WINDOW_ACTIVATED,
+AS_SCREENMODE_CHANGED,
+
 // Graphics calls
 // Are these TRANSACTION codes needed ?
 AS_BEGIN_TRANSACTION,