diff --git a/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts b/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts
index af6ba1145eb..108b766f61b 100644
--- a/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts
+++ b/src/vs/workbench/contrib/chat/browser/chatListRenderer.ts
@@ -622,7 +622,7 @@ export class ChatListItemRenderer extends Disposable implements ITreeRenderer<Ch
 		const container = $('.chat-used-context', undefined, buttonElement);
 		collapseButton.label = referencesLabel;
 		collapseButton.element.append(iconElement);
-
+		this.updateAriaLabel(collapseButton.element, referencesLabel, element.usedReferencesExpanded);
 		container.classList.toggle('chat-used-context-collapsed', !element.usedReferencesExpanded);
 		listDisposables.add(collapseButton.onDidClick(() => {
 			iconElement.classList.remove(...ThemeIcon.asClassNameArray(icon(element)));
@@ -630,6 +630,7 @@ export class ChatListItemRenderer extends Disposable implements ITreeRenderer<Ch
 			iconElement.classList.add(...ThemeIcon.asClassNameArray(icon(element)));
 			container.classList.toggle('chat-used-context-collapsed', !element.usedReferencesExpanded);
 			this._onDidChangeItemHeight.fire({ element, height: templateData.rowContainer.offsetHeight });
+			this.updateAriaLabel(collapseButton.element, referencesLabel, element.usedReferencesExpanded);
 		}));
 
 		const ref = listDisposables.add(this._contentReferencesListPool.get());
@@ -665,6 +666,10 @@ export class ChatListItemRenderer extends Disposable implements ITreeRenderer<Ch
 		};
 	}
 
+	private updateAriaLabel(element: HTMLElement, label: string, expanded?: boolean): void {
+		element.ariaLabel = expanded ? localize('usedReferencesExpanded', "{0}, expanded", label) : localize('usedReferencesCollapsed', "{0}, collapsed", label);
+	}
+
 	private renderPlaceholder(markdown: IMarkdownString, templateData: IChatListItemTemplate): IMarkdownRenderResult {
 		const codicon = $('.interactive-response-codicon-details', undefined, renderIcon({ id: 'sync~spin' }));
 		codicon.classList.add('interactive-response-placeholder-codicon');