iFrame URL used outside pipedriver,the sdk didn't work,how can i do?

(async function() {
const sdk = await new AppExtensionsSDK().initialize();
sdk.execute(AppExtensionsSDK.Command.GET_SIGNED_TOKEN).then((res)=>{
debugger
})
})();

Hi,

AppExtensionsSDK will not work on pages outside Pipedrive, meaning it has to be initialized inside the iframe that is rendered as CustomUI extension.
What is the purpose of using it outside Pipedrive?