AIContainerSidebar

ClassicEditor
	.create( {
		attachTo: document.querySelector( '#editor' ),
		// ... Other configuration options ...
		ai: {
			container: {
				type: 'sidebar',

				// Existing DOM element to use as the container for the AI user interface.
				element: document.querySelector( '#ai-sidebar-container' ),

				// (Optional) The preferred side of the element to position the tab buttons.
				side: 'right'
			},
		}
	} )
	.then( ... )
	.catch( ... );