Why does this setting block Zendesk Live Chat migration?

Why does this setting prevent the Web Messaging integration from initializing after migrating from Zendesk Chat?

We are in the middle of a complex migration from Zendesk to Genesys Cloud for a client based in Paris. The goal is to map their existing Zendesk ticketing workflows directly to Genesys Cloud interactions and reporting structures. In Zendesk, we had a simple custom field mapping for chat transcripts that fed directly into their analytics dashboard. We attempted to replicate this by creating a custom attribute in Genesys Cloud and linking it to the Web Messaging channel.

However, when we try to activate the Web Messaging integration via the admin console or the API, we get a hard stop. The error returned is a 400 Bad Request on the /api/v2/integrations/webmessaging endpoint. The response body indicates that the configuration object is missing a required webchat_id or that the associated domain is not verified, even though we followed the Zendesk-to-GC migration guide step-by-step.

Environment details:

  • Genesys Cloud EU region
  • Zendesk Support v2 API
  • Genesys Cloud Admin UI latest version
  • Browser: Chrome 120

In Zendesk, this process was essentially drag-and-drop for custom fields. In Genesys Cloud, it feels like we are hitting a wall with the initial setup. The documentation mentions that Web Messaging requires a specific tenant configuration before any custom attributes can be bound to the interaction stream. We have verified that our domain is verified in the Genesys Cloud admin panel.

Is there a specific order of operations required for migrating custom chat attributes? Or is this a known issue when moving from a ticket-centric model (Zendesk) to an interaction-centric model (Genesys Cloud)? We need to ensure our reporting on chat volume and sentiment analysis matches our previous Zendesk dashboards exactly. Any insights on bypassing this 400 error would be greatly appreciated. We are stuck on this for two days now.