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sunpeak API

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Overview

The useUserAgent hook returns the host application identifier string from McpUiHostContext.userAgent. This is an opaque string set by the host — not the browser’s navigator.userAgent. It is a convenience wrapper around useHostContext.
The format and content of this string is host-defined. Not all hosts report a user agent, so the value may be undefined.
Known host values:
HostuserAgent value
ChatGPT"chatgpt"
ClaudeBrowser user-agent string (e.g. "Mozilla/5.0 ...")

Wraps onhostcontextchanged

MCP Apps SDK reference

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Import

import { useUserAgent } from 'sunpeak';

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Signature

function useUserAgent(): string | undefined

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Returns

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return
string | undefined
The host application identifier string, or undefined if the host does not report one.

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Usage

import { useUserAgent } from 'sunpeak';

function MyResource() {
  const userAgent = useUserAgent();

  return <p>Host: {userAgent ?? 'unknown'}</p>;
}