The largest MCP revision changes how you run it, not what it does
The biggest overhaul of the protocol wiring agents into enterprise systems makes almost nothing more capable. It makes MCP something a firm can run on ordinary infrastructure and govern.
How we build
The largest revision of the protocol since launch
The protocol becomes stateless. The handshake and the session header both go, so any request can land on any instance and a server that needed sticky sessions and a shared session store now runs behind a plain round-robin load balancer. State does not vanish. A tool mints a handle and the model passes it back as an ordinary argument, which makes the state visible rather than hidden. New required headers let a gateway route and rate-limit on the operation without reading the body.
We tell a client that almost none of this makes an agent more capable. The model did not move. The plumbing did, and what a protocol needing specialist deployment gains is commodity infrastructure, a deprecation contract a platform team can plan against, and one audit path for every agent action. The cost is stated plainly, in breaking changes and a numbered migration. That migration is not something anybody downloads. It is planned engineering and governance work, owned by whoever runs the servers.