Expanding the MCP Maintainer Team

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. ...

April 8, 2026 · 3 min · David Soria Parra (Lead Maintainer)

Tool Annotations as Risk Vocabulary: What Hints Can and Can't Do

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. ...

March 16, 2026 · 11 min · Ola Hungerford (Maintainer), Sam Morrow (GitHub), Luca Chang (AWS)

The 2026 MCP Roadmap

MCP’s current spec release came out in November 2025. We haven’t cut a new version since, but the project hasn’t stood still. Over the past year MCP has moved well past its origins as a way to wire up local tools. It now runs in production at companies large and small, powers agent workflows, and is shaped by a growing community through Working Groups, Spec Enhancement Proposals (SEPs), and a formal governance process. None of that is news, but it’s the foundation we’re building on. ...

March 9, 2026 · 6 min · David Soria Parra (Lead Maintainer)

MCP Apps - Bringing UI Capabilities To MCP Clients

Today, we’re announcing that MCP Apps are now live as an official MCP extension. Tools can now return interactive UI components that render directly in the conversation: dashboards, forms, visualizations, multi-step workflows, and more. This is the first official MCP extension, and it’s ready for production. We proposed MCP Apps last November, building on the amazing work of MCP-UI and the OpenAI Apps SDK. We were excited to partner with both OpenAI and MCP-UI to create a shared open standard for providing affordances for developers to include UI components in their MCP clients. ...

January 26, 2026 · 9 min · MCP Core Maintainers

January MCP Core Maintainer Update

A lot has happened since we first released MCP. We wrapped up 2025 with a major spec update and the momentum hasn’t slowed down. None of it would have happened without the community: every PR, every issue filed, every server and client built. That energy is what keeps MCP moving forward. To keep that momentum going, the Core Maintainer team is evolving as well. Departing Core Maintainers First, some news. Inna Harper and Basil Hosmer will be stepping away from the Core Maintainer team to focus on other projects. ...

January 23, 2026 · 4 min · David Soria Parra (Lead Maintainer)

Exploring the Future of MCP Transports

When MCP first launched in November of 2024, quite a few of its users relied on local environments, connecting clients to servers over STDIO. As MCP became the go-to standard for LLM integrations, community needs evolved, leading to the build-out of infrastructure around remote servers. There’s now growing demand for distributed deployments that can operate at scale. The Streamable HTTP transport was a significant step forward, enabling remote MCP deployments and unlocking new use cases. However, as enterprise deployments scale to millions of daily requests, early adopters have encountered practical challenges that make it difficult to leverage existing infrastructure patterns. The friction of stateful connections has become a bottleneck for managed services and load balancing. ...

December 19, 2025 · 7 min · Kurtis Van Gent (Transport WG Maintainer), Shaun Smith (Transport WG Maintainer)

MCP joins the Agentic AI Foundation

Today marks a major milestone for the Model Context Protocol. Anthropic is donating MCP to the Agentic AI Foundation, a directed fund under the Linux Foundation. MCP will become a founding project of the newly created foundation. In one year, MCP has become one of the fastest-growing and widely-adopted open-source projects in AI: Over 97 million monthly SDK downloads, 10,000 active servers and first-class client support across major AI platforms like ChatGPT, Claude, Cursor, Gemini, Microsoft Copilot, Visual Studio Code and many more. ...

December 9, 2025 · 2 min · David Soria Parra (Lead Core Maintainer)

One Year of MCP: November 2025 Spec Release

Today, MCP turns one year old. You can check out the original announcement blog post if you don’t believe us. It’s hard to imagine that a little open-source experiment, a protocol to provide context to models, became the de-facto standard for this very scenario in less than twelve months. But not only do we hit the first anniversary milestone today - we’re also releasing a brand-new MCP specification version. Before we get to the details of what’s new, let’s do a bit of a retrospective. ...

November 25, 2025 · 21 min · MCP Core Maintainers

Adopting the MCP Bundle format (.mcpb) for portable local servers

The MCP Bundle format (MCPB) is now part of the Model Context Protocol project. This distribution format simplifies how developers package and share local MCP servers, enabling users to install them across any compatible client, including the Claude desktop app, Claude Code, and MCP for Windows. What are MCP Bundles? MCP Bundles are ZIP archives containing a local MCP server and a manifest.json that describes the server and its capabilities. The format is similar to Chrome extensions (.crx) or VS Code extensions (.vsix), enabling end users to install local MCP servers with a single click. ...

November 21, 2025 · 3 min · David Soria Parra (MCP Lead Maintainer), Joan Xie (MCPB Maintainer)

Server Instructions: Giving LLMs a user manual for your server

Many of us are still exploring the nooks and crannies of MCP and learning how to best use the building blocks of the protocol to enhance agents and applications. Some features, like Prompts, are frequently implemented and used within the MCP ecosystem. Others may appear a bit more obscure but have a lot of influence on how well an agent can interact with an MCP server. Server instructions fall in the latter category. ...

November 3, 2025 · 9 min · Ola Hungerford (Maintainer)