Type Alias AppOptions

Type Declaration

• OptionalallowUnsafeEval?: boolean

  Allow code paths that require CSP unsafe-eval (e.g. new Function()).

  Views typically run under a strict CSP without unsafe-eval. Zod's JIT object parser uses new Function() and throws on the first message parse under such a policy. By default (allowUnsafeEval: false) the App constructor sets z.config({ jitless: true }) so the SDK works out of the box under the spec's default CSP. Set allowUnsafeEval: true to skip that and keep the faster JIT path when the host's CSP permits unsafe-eval.

  Default

  false
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• OptionalautoResize?: boolean

  Automatically report size changes to the host using ResizeObserver.

  When enabled, the App monitors document.body and document.documentElement for size changes and automatically sends ui/notifications/size-changed notifications to the host.

  Default

  true
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• Optionalstrict?: boolean

  Throw on detected misuse instead of logging a console warning.

  Currently this affects calling host-bound methods (e.g. callServerTool, sendMessage) before connect has completed the ui/initialize handshake. With strict: false (default) a console.warn is emitted; with strict: true an Error is thrown.

  Remarks

  Throwing will become the default in a future release.

  Default

  false
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• OptionalwebMcpBridge?: boolean

  Bridge tools between the Apps SDK and WebMCP, in both directions:

  • tools registered with registerTool are mirrored into document.modelContext when the document provides one, so WebMCP-enabled hosts discover them without speaking the Apps tools/list channel (the tools/list / tools/call wire path is unaffected either way);
  • tools the page registered on document.modelContext are served over the Apps tools/list / tools/call channel, so WebMCP-authored Views work on MCP Apps hosts that do not provide WebMCP themselves. Tools registered with registerTool win on name collisions, and tools the App itself mirrored into WebMCP are never echoed back.

  Pass false to disable the bridge.

  Default

  true
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