Web Messaging widget: Passing custom attributes for authenticated users

Hey folks,

Trying to inject custom guest attributes into the Web Messaging widget for logged-in users, but the data isn’t showing up in the interaction summary. We’ve got the init code looking like this:

GCWebMessaging.init({
 organizationId: 'org-123',
 guestAttributes: {
 customerId: 'user-99',
 tier: 'premium'
 }
});

The widget loads fine, but when the agent opens the chat, those attributes are missing from the context. Am I missing a specific API call to persist these attributes before the session starts?