MCP publishes the Apps Working Group charter covering the interactive UI extension

The Model Context Protocol project published the charter for its MCP Apps Working Group on 2026-08-12, when pull request #3194 by Ido Salomon merged the document into the community docs at modelcontextprotocol.io. The group "defines, evolves, and maintains the official extension for interactive user interfaces over MCP": the MCP Apps extension specification and related SEPs under the io.modelcontextprotocol/ui namespace, the @modelcontextprotocol/ext-apps SDK and reference implementations, the extension's security model, and conformance requirements for apps and hosts.

The charter names three leads: Ido Salomon (MCP-UI), Liad Yosef (MCP-UI / Ora), and Olivier Chafik (Anthropic), with Anton Pidkuiko (Anthropic) and Max Stoiber (OpenAI) as working-group members. Headline workstreams listed as in progress include protocol alignment and versioning of the extension SDK, reusable views across tools and servers, formalizing the security model and sandboxing, and an official conformance validator.

The group itself predates the page: the charter's own changelog dates the foundational proposal SEP-1865, which unified the MCP-UI and OpenAI Apps SDK approaches, to 2025-11-21, the first working-group meeting to 2025-12-17, the initial stable MCP Apps extension specification to 2026-01-26, and the initial charter to 2026-05-21. Publication in the community docs places the Apps group alongside the previously chartered groups, including the Agents Working Group whose charter was published on 2026-08-05.