@jeffyaw there's a few things mixed in here that I would recommend pulling apart and treating as separate contributions. Regarding sessions, there will be changes happening here - would recommend checking with the Transports Working Group on Discord (cc: @kurtisvg @CaitieM20) on the latest here.

Additionally, the server discovery piece is likely its own SEP related to #2127 - that should be your starting point for this work.

Lastly, on the general deployment guidelines, we should have that as a separate article/guideline - that doesn't require a SEP and can move a lot faster since it's just a set of recommendations. If you can pull it into a separate PR and align it with the rest of the docs, we can review it much quicker.

Thank you @localden — this is very helpful. I'll split this into the right pieces:

1. Sessions — I'll join the Transports Working Group on Discord and share what we've learned about session affinity routing there. Happy to contribute to whatever direction the group takes.

2. Server discovery — I'll open a separate contribution building on SEP-2127: MCP Server Cards - HTTP Server Discovery via .well-known #2127 rather than proposing a competing approach.

3. Deployment guidelines — I'll pull the proxy/deployment recommendations into a separate docs PR. That section is purely operational guidance (SSE buffering, timeout config, header forwarding, SSRF protection) so it makes sense outside the SEP process.

I'll close this PR once the docs PR is up. Thanks for the direction.