@kristatos
I concur!
There are guidelines outlined by the gsma for an RCS client and from what I read from this reditor there are even Servers outlined in the GSMA docs for sending RCS messages for some carriers.
It seems that SixDigitCode has made some great points for how a RCS client could be built.
From what I see they have a handle on this spec, and it might be worth seeing if they are still around on the internet?
I will post again with the updated documents from the GSMA and work on trying to break them down
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