Capturing gRPC streaming response endpoint

I'm looking for what defines the streaming gRPC endpoint for streamed responses.
When I send a gRPC message the streaming response endpoint is saved.
User A connects and asks a question.
User B connects and asks a similar question.
The server supplies a AI response to the question and streams the answer to both user A and B.
The question I am looking for is what the server can get when either connects as an identify (IP address or whatever) so that answers can be gRPC responses streamed both users.