Model Context Protocol Blog

The release candidate for MCP 2026-07-28 is now available. It is the largest revision of the protocol since launch and delivers on the 2026 roadmap: a stateless core that scales on ordinary HTTP infrastructure extensions including server-rendered UIs through MCP Apps and long-running work through the Tasks extension authorization that aligns more closely with OAuth and OpenID Connect deployments a formal deprecation policy so the protocol can evolve without breaking what you’ve built, and many other changes. ...

I’m happy to share two updates to the maintainer team: Clare Liguori is joining the Core Maintainer group, and Den Delimarsky is joining me as a Lead Maintainer. When we introduced the MCP governance model last summer, the goal was to make sure the protocol could keep growing without any one person becoming a bottleneck. That has held up well through two specification releases, the move to the Agentic AI Foundation (AAIF), and a steady increase in SEP volume, and these changes give the project the leadership capacity it needs for what comes next. ...

MCP tool annotations were introduced nearly a year ago as a way for servers to describe the behavior of their tools — whether they’re read-only, destructive, idempotent, or reach outside their local environment. Since then, the community has filed five independent Specification Enhancement Proposals (SEPs) proposing new annotations, driven in part by a sharper collective understanding of where risk actually lives in agentic workflows. This post recaps where tool annotations are today, what they can and can’t realistically do, and offers a framework for evaluating new proposals. ...