You are in a lemmy instance talking about it, which is why the people reading a post about a version update to it, know what it is.
Not to mention that this post is specifically in the Home Assistant-community, which describes the FOSS, local control and privacy aspects of it in the community description.
Were they not going to release the songs as well? They just started with the metadata?
ETA: Yes, this is from their blog post about it: