There are however little more than tech demos for it. There's still a significant body of unresolved questions. Theres very limited amount of effort going in. But there are some very nice libraries too, such as https://github.com/youtube/openscreen-rs .

Not an answer for most people for today, but if folks are feeling agentic, this is where I would burn my tokens. Your timing is actually quite incredible; I picked up my project again & have been burning the last tokens of my weekly quota on open screen protocol today!

(Don't get me started on what a frelling turd show MatterCast is. Last I checked it was for native apps, and had no means to distribute or find programs, only could work with apps already on the castee. Miserable evil capture-computing shizzle, with zero aspirations to ever allow the just works interoperability that made Cast so amazing. Truly captured device ecosystem, of Official Partners anti-consumer villainy. Vomitously disgusting, makes me feel much worse about Matter in general seeing how wretched that looks.)