As I mentioned before the python documentation is very laky, and what should be a very simple and streamline operation is becoming a tedious trial and error process.
What is the proper way of translating this yaml:
Good for you, but please share your solution in this community so that others with a similar problem ,landing on this post in the future, can use the solution as well. See: I’ve solved it!
Turns out that the error was not pointing that the property were not allowed, no, it was trying to say (in a confusing manner) that the value of the property was incorrect. That was the first tricky part
What is the other tricky part? the name/id of the entity. First confusing part is that the name of the entity to set the volume is different from the name you use to to play a sound using the notify service. On top of that, for some reason the name/id of the device for the media player needs to be prefixed with media_player., while the one for the notification does notr.
Here you can see one example with the two different names: