Genesys Cloud Web Messaging SDK: Custom guest attributes failing for authenticated users on widget deploy

NICE CXone API & Integrations
1

Just noticed that custom guest attributes are not persisting for authenticated users when deploying the widget via the Genesys Cloud Web Messaging SDK. The setGuestAttributes method returns success, but the /api/v2/conversations/messaging endpoint shows an empty attributes object in the guest payload.

“Authenticated users should pass custom attributes through the guest identity provider configuration.”

Here is the JSON payload I am sending:

{
 "guestName": "Tom Lim",
 "attributes": {
 "userId": "12345",
 "role": "admin"
 }
}

Is there a specific SDK version requirement or configuration step I am missing?

2

The problem here is timing. setGuestAttributes fires before the conversation ID exists. 1. Wait for conversationCreated. 2. Call setConversationAttributes instead. 3. Use application/json. Do not trust the guest payload for auth users. Svelte devs know state updates need triggers.

sdk.on('conversationCreated', (ev) => {
 sdk.setConversationAttributes(ev.conversationId, { role: 'vip' });
});
3

this looks like a scope issue in architect. setGuestAttributes only works for anonymous. for auth users, use the identity provider to merge attributes. ensure view:interaction scope exists. i use {{conversation.participants[?type == 'agent'].attributes.custom}} to verify persistence.

4

The way I solve this is by injecting attributes via the FastAPI proxy instead of the SDK. The widget payload often strips auth data. Send this to /api/v2/conversations/messaging:

{
 "guest": {
 "attributes": {
 "custom_key": "value"
 }
 }
}

This bypasses client-side timing issues entirely.

5

if i remember correctly… pushing auth user attributes via the client sdk is a race condition waiting to happen. the widget often fires before the identity token is fully resolved by the gateway. while the suggestion above about using setConversationAttributes is technically sound, it fails silently if the event listener isn’t bound before initialization.

for auth flows, i usually bypass the widget’s attribute methods entirely. i use a lambda layer with the @genesyscloud/genesyscloud sdk to patch the conversation metadata server-side. this ensures the attributes are locked in before the agent sees the interaction.

const client = new PureCloudPlatformClientV2();
client.conversationsApi.patchConversationsMessagingConversation(
 convId, 
 { attributes: { custom: val } }
);

this approach is idempotent and avoids the CORS headaches mentioned earlier. just ensure your lambda has the view:interaction scope. don’t trust client-side state for anything that impacts routing or compliance.