The sonarr native integration allows you to add your sonarr instances that are available publicly on the internet to your listrr account. The added sonarr instances can be used to add your lists automatically via the
Custom Lists feature available in sonarr.
This feature makes it easier for users with many lists to automatically add them to their instances without manually adding each list one by one.
How to add a list
Take a look at the listrr.pro to Sonarr bridge. It will automatically import your lists into your Sonarr instance. https://github.com/TheUltimateC0der/listrr.pro.Sonarr
You can also find the documentation for setting it up here