MCP Apps

What MCP Apps enables

MCP Apps brings interactive interfaces directly into an assistant. An MCP tool can provide a product view, a variant selector or a configurator. Customers can make selections during the conversation without describing every input in a message.

Connections with other protocols

• MCP Apps extends MCP: a tool call connects to an appropriate HTML interface that the host displays within the conversation.
• AXP also describes embedded product experiences and adds structured commerce data. MCP Apps provides the general mechanism for interactive tool interfaces.

Versions and licence

Published version

2026-01-26 · 2026-01-26

Working draft

—

SDK versions and host support develop independently of the specification version.

Licence / terms

Repository transitioning from MIT to Apache-2.0; some older contributions remain MIT. Documentation outside the specification: CC-BY-4.0. Package metadata still lists MIT; consult the licence files of the release used.
Licence and terms ↗

An example flow

1. An MCP tool references a UI resource in its description, such as a variant selector.
2. The host loads the interface and displays it in an embedded, isolated area of the conversation.
3. The customer selects a variant. The interface can call MCP server tools as part of this interaction.
4. The result feeds back into the interface and the ongoing conversation.

SDKs and examples

These libraries and examples help you get started. Each entry lists the language, package and supported version.

Practical integration

• The application needs a host supporting the Apps extension. The UI resource is offered alongside the relevant MCP tool.
• The SDK includes components for servers, interfaces and host integration. The version listed here requires Node.js 20+ and MCP v2 peer dependencies.

Related protocols

Original sources

• Official overview ↗
• Specification and SDK ↗
• Package versions ↗
• Stable specification 2026-01-26 ↗
• SDK release 2.0.3 ↗