diff --git a/param-docs/parameter-pages/GPIO/MainTopicMQTT.md b/param-docs/parameter-pages/GPIO/MainTopicMQTT.md
index e03e755..19ce2b8 100644
--- a/param-docs/parameter-pages/GPIO/MainTopicMQTT.md
+++ b/param-docs/parameter-pages/GPIO/MainTopicMQTT.md
@@ -4,4 +4,5 @@ Default Value: `wasserzaehler/GPIO`
 !!! Note
     This parameter is not accessible through the Web Interface Configuration Page!
 
-Please fill me with an explanation and useful links
+The GPIO Interface is prepared to report it's status and status changes as a MQTT topic. With this parameter you configure the MQTT main topic, under which the status is published.
+As this parameter is still experimental it can only be set manually in the `config.ini` itself and has not been tested in detail so far.