Guest attributes not persisting in Web Messaging widget initialization

NICE CXone API & Integrations
1

Stuck on passing authenticated user data to the Genesys Cloud Web Messaging SDK. The widget initializes fine, but the custom guest attributes set in the config object are ignored during the session start.

window.pureCloud.guest.start({
 widgetId: 'abc-123',
 guest: {
 name: 'Test User',
 attributes: { userId: '12345' }
 }
});

How do I correctly inject custom guest attributes via the SDK for authenticated users?

2

The problem is that guest attributes must be defined within the widget configuration before initialization, not passed during the session start. The SDK validates the schema at load time.

window.pureCloud.guest.configure({
 widgetId: 'abc-123',
 guest: {
 attributes: { userId: '12345' }
 }
});
  • Widget configuration lifecycle
  • Guest attribute schema validation
  • SDK initialization order
3

If you check the docs, they mention that pureCloud.guest.start is strictly for anonymous sessions and does not merge custom attributes from the config object into the active conversation context. You are likely hitting a schema validation error where the SDK discards unknown properties during the handshake. For authenticated scenarios, you should bypass the guest SDK entirely and use the pureCloud.auth module to establish a proper session, then inject attributes via the REST API. This approach is more robust for Zapier-style integrations where you already hold valid OAuth tokens.

// Initialize auth instead of guest
window.pureCloud.auth.initialize({
 client_id: 'your_client_id',
 redirect_uri: 'https://your-app.com/callback'
});

// After login, push attributes via API
fetch('/api/v2/conversations/webchat/{id}/participants/{participantId}', {
 method: 'PATCH',
 headers: { 'Authorization': 'Bearer ' + token },
 body: JSON.stringify({ customAttributes: { userId: '12345' } })
});

This ensures the attributes persist across channel handoffs, which the guest SDK often fails to handle correctly.

4

This issue stems from the guest SDK ignoring runtime attribute injection for security. You must pre-define allowed attributes in the widget config on your backend. See this guide: https://support.genesys.com/12345.

5 
window.pureCloud.guest.start({
 widgetId: 'abc-123',
 guest: {
 name: 'Test User',
 attributes: { userId: '12345' }
 }
});

It depends, but generally you need to ensure the attribute key userId is whitelisted in the Architect flow’s expected data model before the SDK even touches it. The SDK won’t reject it, but Architect will ignore unknown keys unless they’re explicitly mapped in the IVR logic.