{
  "title": "MCP Apps",
  "description": "Stable MCP extension for interactive interfaces returned by tools and rendered by compatible hosts.",
  "slug": "mcp-apps",
  "locale": "en",
  "seoTitle": "MCP Apps compatibility reference — Can My Agent Use",
  "socialTitle": "MCP Apps compatibility",
  "socialDescription": "Host roles, stable revision, and evidence boundaries for MCP Apps.",
  "llmSummary": "MCP Apps is an MCP extension for ui resources and sandboxed interactive interfaces. A host can support MCP tools without supporting MCP Apps.",
  "audience": "Architects and engineers evaluating agent interoperability.",
  "contentKind": "specification",
  "status": "published",
  "tags": [
    "mcp",
    "ui",
    "apps",
    "protocol"
  ],
  "updated": "2026-08-28T00:00:00.000Z",
  "published": "2026-08-28T00:00:00.000Z",
  "authority": "MCP project",
  "revision": "2026-01-26",
  "maturity": "stable extension",
  "structure": "MCP extension, ui resource, and sandboxed frame",
  "sourceId": "S-039",
  "canonicalUrl": "https://modelcontextprotocol.io/extensions/apps/specification",
  "summary": "Return an interactive interface from an MCP tool for rendering inside a compatible host.",
  "roles": [
    "host",
    "server",
    "app"
  ],
  "aliases": [
    "MCP UI",
    "MCP interactive apps"
  ],
  "body": "MCP Apps defines an interactive UI layer on top of MCP. The host discovers a declared UI resource, renders it in an isolated frame, and mediates communication with the tool and host.\n\nTool calling and app rendering remain separate catalog capabilities. Host listing, plan availability, developer-mode access, sandbox behavior, and extension revision should remain visible in the evidence.",
  "html": "/specs/mcp-apps",
  "markdown": "/specs/mcp-apps.md",
  "json": "/api/v1/specs/mcp-apps.json"
}