Internally in MQTT Transmission we look for tags being added, moved, or deleted by using a TagStructureListener (TagStructureListener) to detect these events. In turn we use this to control the ‘Refresh Required’ boolean tag. We could potentially use this in MQTT Engine to define a clearable tag - but this isn’t there today. I like the idea and will add it to our backlog.
For now, you can at least listen for new Edge Nodes in the [MQTT Engine]Engine Info/Edge Nodes folder. But, it seems you want more than just what this has to offer today.