diff --git a/src/vs/workbench/api/common/extHostTypes.ts b/src/vs/workbench/api/common/extHostTypes.ts
index 9d6428ebcdd..4bbfe4c7787 100644
--- a/src/vs/workbench/api/common/extHostTypes.ts
+++ b/src/vs/workbench/api/common/extHostTypes.ts
@@ -4351,9 +4351,11 @@ export class LanguageModelChatUserMessage {
 
 export class LanguageModelChatAssistantMessage {
 	content: string;
+	name?: string;
 
-	constructor(content: string) {
+	constructor(content: string, name?: string) {
 		this.content = content;
+		this.name = name;
 	}
 }
 
diff --git a/src/vscode-dts/vscode.proposed.languageModels.d.ts b/src/vscode-dts/vscode.proposed.languageModels.d.ts
index 9cd0f8c1ccb..98a61ecde42 100644
--- a/src/vscode-dts/vscode.proposed.languageModels.d.ts
+++ b/src/vscode-dts/vscode.proposed.languageModels.d.ts
@@ -79,12 +79,18 @@ declare module 'vscode' {
 		 */
 		content: string;
 
+		/**
+		 * The optional name of a user for this message.
+		 */
+		name: string | undefined;
+
 		/**
 		 * Create a new assistant message.
 		 *
 		 * @param content The content of the message.
+		 * @param name The optional name of a user for the message.
 		 */
-		constructor(content: string);
+		constructor(content: string, name?: string);
 	}
 
 	/**