From 1bee97a5c062a6b522effc6e82cb01d10291b907 Mon Sep 17 00:00:00 2001 From: Liad Yosef Date: Sun, 26 Jul 2026 02:05:19 +0300 Subject: [PATCH] docs(community): add MCP Apps Working Group charter Adds the charter for the MCP Apps Working Group following the group charter template, and registers it in the docs navigation. The WG owns the MCP Apps extension (SEP-1865, Final), which defines predeclared UI resources under the ui:// scheme, tool-to-UI association via metadata, and bi-directional host/UI messaging over MCP's JSON-RPC base protocol. The specification and SDK live in the ext-apps repository. Scope, work items, and membership are grounded in the extension's live issues and the group's public rolling agenda, which has recorded tri-weekly meetings since 2025-12-17. --- docs/community/working-groups/mcp-apps.mdx | 183 +++++++++++++++++++++ docs/docs.json | 1 + 2 files changed, 184 insertions(+) create mode 100644 docs/community/working-groups/mcp-apps.mdx diff --git a/docs/community/working-groups/mcp-apps.mdx b/docs/community/working-groups/mcp-apps.mdx new file mode 100644 index 000000000..c1c53160c --- /dev/null +++ b/docs/community/working-groups/mcp-apps.mdx @@ -0,0 +1,183 @@ +--- +title: MCP Apps Charter +description: Charter for the MCP Apps Working Group. +--- + +## Group Type + +**Working Group** + +## Mission Statement + +The MCP Apps Working Group defines how MCP servers deliver interactive user +interfaces to hosts. The group emerged from the convergence of MCP-UI and the +OpenAI Apps SDK into a single open standard via +[SEP-1865](/seps/1865-mcp-apps-interactive-user-interfaces-for-mcp) +(Extensions Track, Final), which introduces predeclared UI resources (the +`ui://` URI scheme), tool-to-UI association through metadata, and +bi-directional host/UI communication over MCP's JSON-RPC base protocol. The WG +produces specification extensions, SDKs, reference implementations, and host +guidance because interactive UI touches the protocol spec, SDK surface, host +security model, and client rendering behavior across the ecosystem (Claude, +ChatGPT, VS Code, Goose, Postman, and others). + +## Scope + +### In Scope + +- **Specification Work**: The MCP Apps Extension + ([modelcontextprotocol/ext-apps](https://github.com/modelcontextprotocol/ext-apps)) + and related SEPs, including UI resource declaration, tool metadata, lifecycle + and messaging (`ui/*` methods and notifications), and content-type profiles + (initially `text/html;profile=mcp-app`) under the + `io.modelcontextprotocol/ui` namespace. +- **Future Content Types & Rendering Targets**: Non-HTML view mimetypes, + container-agnostic rendering, and declarative or generative UI directions, + including A2UI interoperability. +- **SDKs & Reference Implementations**: The MCP Apps SDK + (`@modelcontextprotocol/ext-apps`), example servers, the reference host, and + host integration references demonstrating secure rendering and + bi-directional communication. +- **Security Model**: Sandboxing, origin isolation, CSP guidance, auditability + of UI-initiated actions, and threat-model documentation for host + implementers. +- **Conformance**: Host compatibility tests, an official MCP App validator, and + the definition of what "spec-conformant" means for both apps and hosts. +- **Cross-Cutting Concerns**: Coordination with the Registry WG (app + discoverability and metadata), Agents WG (UI in agentic loops), Security IG + (sandboxing and UI-initiated tool calls), SDK WG and SDK maintainers + (per-language support), and external projects (A2UI, AG-UI, and community + frameworks). +- **Documentation**: Specification sections and guidance for app authors and + host implementers. + +### Out of Scope + +- **Host-specific design systems**: Hosts control final look-and-feel. The WG + standardizes the contract, not visual design. +- **Client implementation mandates**: We document rendering and security + patterns but cannot require specific host behavior beyond spec conformance. +- **General agent orchestration**: Agent loops and sub-agent coordination + belong to the Agents WG. This WG covers only the UI surface. +- **Core protocol changes**: Changes to base MCP semantics are proposed through + the [SEP process](/community/sep-guidelines) and owned by the relevant group + or Core Maintainers. This WG owns the Apps extension, not the base protocol. + +### Related Groups + +- **Agents WG**: interactive UI within agentic flows and task lifecycles. +- **[Registry WG](/community/working-groups/registry)**: app metadata, + discovery, and distribution. +- **[Security IG](/community/interest-groups/security)**: sandboxing model and + review of UI-initiated actions. +- **[SDK WG](/community/working-groups/sdk)**: per-language MCP Apps support + and SDK consistency. + +## Leadership + +| Role | Name | Organization | GitHub | Term | +| ---- | ----------- | ------------ | ------------------------------------ | ------- | +| Lead | Ido Salomon | MCP-UI | [@idosal](https://github.com/idosal) | Initial | +| Lead | Liad Yosef | MCP-UI / Ora | [@liady](https://github.com/liady) | Initial | + +## Authority & Decision Rights + +| Decision Type | Authority Level | +| ----------------------------------- | ------------------------------------------------------ | +| Meeting logistics & scheduling | WG Leads (autonomous) | +| Proposal prioritization within WG | WG Leads (autonomous) | +| SEP triage & closure (in scope) | WG Leads (autonomous, with documented rationale) | +| Technical design within scope | WG consensus | +| Spec changes (additive) | WG consensus → Core Maintainer approval | +| Spec changes (breaking/fundamental) | WG consensus → Core Maintainer approval + wider review | +| Scope expansion | Core Maintainer approval required | +| WG Member approval | WG Member sponsors | + +## Membership + +| Name | Organization | GitHub | Discord | Level | +| ------------------ | -------------------------- | ---------------------------------------------------------- | ------- | ----------- | +| Ido Salomon | MCP-UI | [@idosal](https://github.com/idosal) | | Lead | +| Liad Yosef | MCP-UI / Ora | [@liady](https://github.com/liady) | | Lead | +| Olivier Chafik | Anthropic / MCP Maintainer | [@ochafik](https://github.com/ochafik) | | WG Member | +| Jonathan Hefner | MCP Maintainer | [@jonathanhefner](https://github.com/jonathanhefner) | | WG Member | +| Anton Pidkuiko | MCP Maintainer | [@antonpk1](https://github.com/antonpk1) | | WG Member | +| Nick Cooper | OpenAI | [@nickcoai](https://github.com/nickcoai) | | WG Member | +| Max Stoiber | OpenAI | [@mstoiber-oai](https://github.com/mstoiber-oai) | | Participant | +| Dominic Farolino | Google / Chromium | [@domfarolino](https://github.com/domfarolino) | | Participant | +| Cameron Yick | Datadog | [@hydrosquall](https://github.com/hydrosquall) | | Participant | +| Frédéric Barthelet | Alpic | [@fredericbarthelet](https://github.com/fredericbarthelet) | | Participant | +| Ola Hungerford | Nordstrom | [@olaservo](https://github.com/olaservo) | | Participant | +| Yann Jouanin | | [@yannj-fr](https://github.com/yannj-fr) | | Participant | + +## Operations + +| Meeting | Frequency | Duration | Purpose | +| --------------- | -------------------------------- | -------- | ------------------------------------------------------------------------ | +| Working Session | Tri-weekly (Wednesday, 08:00 PT) | 60 min | Spec review, SDK coordination, host implementation feedback; open to all | +| Office Hours | Monthly (planned) | 30 min | Open Q&A for app authors, host implementers, and newcomers | + +Meetings are published at +[meet.modelcontextprotocol.io](https://meet.modelcontextprotocol.io) under the +`#mcp-apps-wg` tag. Agendas and notes are maintained as a public rolling +document, the +[MCP Apps Workgroup Agenda](https://docs.google.com/document/d/103S6IjN9D80ntbPIcK3mP_ZWdeFom2Mq8qpkpIsXRVI/edit), +and are posted per the MCP meeting policy. The group has met since +2025-12-17. + +Discord: `#mcp-apps-wg` + +## Resources + +- Extension specification & SDK: + [modelcontextprotocol/ext-apps](https://github.com/modelcontextprotocol/ext-apps) + (npm: `@modelcontextprotocol/ext-apps`) +- SEP: [SEP-1865](/seps/1865-mcp-apps-interactive-user-interfaces-for-mcp) +- Ecosystem docs: [MCP Apps overview](/extensions/apps/overview) and + [Build an MCP App](/extensions/apps/build) +- Documentation & API reference: + [apps.extensions.modelcontextprotocol.io](https://apps.extensions.modelcontextprotocol.io/) +- Issue tracker: + [ext-apps issues](https://github.com/modelcontextprotocol/ext-apps/issues) + +## Deliverables & Success Metrics + +### Active Work Items + +Live tracking is in +[ext-apps issues](https://github.com/modelcontextprotocol/ext-apps/issues) and +pull requests. Headline workstreams: + +| Item | Status | Target Date | Champion | +| ---------------------------------------------------------------------------------------------------------------------------------------------------- | ----------- | ----------- | -------------------------------------------------------------------------------------- | +| Spec maintenance & next revision (current: 2026-01-26) | In Progress | | [@idosal](https://github.com/idosal), [@liady](https://github.com/liady) | +| MCP Apps SDK (`@modelcontextprotocol/ext-apps`, stable 1.x) | Maintained | | MCP Apps SDK maintainers | +| Host compatibility & conformance test suite ([#674](https://github.com/modelcontextprotocol/ext-apps/issues/674)) | In Progress | | [@idosal](https://github.com/idosal) | +| Reusable views & view session identity ([#430](https://github.com/modelcontextprotocol/ext-apps/issues/430)) | In Progress | | [@mstoiber-oai](https://github.com/mstoiber-oai), [@idosal](https://github.com/idosal) | +| Rendering architecture: decouple requirements from the double-sandboxed iframe ([#716](https://github.com/modelcontextprotocol/ext-apps/issues/716)) | In Review | | [@domfarolino](https://github.com/domfarolino) | +| Dynamic View Content via embedded resources ([#699](https://github.com/modelcontextprotocol/ext-apps/pull/699)) | Proposal | | [@liady](https://github.com/liady) | +| Views not tied to a specific tool call ([#672](https://github.com/modelcontextprotocol/ext-apps/issues/672)) | In Progress | | [@mstoiber-oai](https://github.com/mstoiber-oai), [@liady](https://github.com/liady) | +| Authoring toolkit: Agent Skills, reference host (`basic-host`), example suite | Maintained | | TBD | + +### Success Criteria + +- Published, stable extension specification (2026-01-26 revision shipped) with + a maintained SDK and reference host, and responsive triage of spec and SDK + issues. +- A conformance suite that host implementers can run, with results published so + app authors know what works where. +- Interoperable MCP Apps running unmodified across multiple major hosts, with + the documented security model adopted by those hosts. +- A clear, specified path for content types beyond HTML. +- MCP Apps established as the standard UI layer of the agentic web: a single + app implementation reaching every MCP host. + +## Changelog + +| Date | Change | +| ---------- | ------------------------------------------------------------------------------------------ | +| 2025-11-21 | SEP-1865 proposed; MCP-UI and OpenAI Apps SDK approaches unified under the MCP Apps banner | +| 2025-12-17 | First MCP Apps Working Group meeting | +| 2026-01-26 | MCP Apps extension specification revision 2026-01-26 published | +| 2026-01-28 | SEP-1865 marked Final and merged | +| 2026-07-26 | Initial charter | diff --git a/docs/docs.json b/docs/docs.json index 74bcb9caa..0360e197c 100644 --- a/docs/docs.json +++ b/docs/docs.json @@ -497,6 +497,7 @@ "community/working-groups/file-uploads", "community/working-groups/inspector-v2", "community/working-groups/interceptors", + "community/working-groups/mcp-apps", "community/working-groups/registry", "community/working-groups/sdk", "community/working-groups/server-card",