Skip to content

docs(community): add MCP Apps Working Group charter #3131

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
liady wants to merge 2 commits into
base: main
Choose a base branch
from
+184 −0
Draft

docs(community): add MCP Apps Working Group charter #3131

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
1bee97a
docs(community): add MCP Apps Working Group charter
liady Jul 25, 2026
ae0ba4d
Merge branch 'main' into mcp-apps-charter
dsp-ant Jul 28, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
183 changes: 183 additions & 0 deletions docs/community/working-groups/mcp-apps.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -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 |
1 change: 1 addition & 0 deletions docs/docs.json
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -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",
Expand Down
Loading