MCP notifications

Tag 5: the server subscribes, once, to the notifications of the caller’s MCP servers; the client answers with one channel response per notification, an error last, and the channel response finish, each relayed to the programs in the container.

The server opens this channel at most once per connection, when a program in the container first makes an MCP exchange of the server. Every channel response is relayed to every MCP session the server serves at the time it arrives.

• The request. The tag byte 5 and nothing more. Request states its form.
• The response. One channel response per notification, an error last when the client sends one, and the channel response finish. Response states the sequence.
• Once. The server does not open this channel a second time on the connection, however the first ended.