diff --git a/comment-sample/src/typings/vscode.proposed.d.ts b/comment-sample/src/typings/vscode.proposed.d.ts
index a1334387..e5b5e7d4 100644
--- a/comment-sample/src/typings/vscode.proposed.d.ts
+++ b/comment-sample/src/typings/vscode.proposed.d.ts
@@ -100,43 +100,43 @@ declare module 'vscode' {
 		/**
 		 * The id of the comment
 		 */
-		commentId: string;
+		readonly commentId: string;
 
 		/**
 		 * The text of the comment
 		 */
-		body: MarkdownString;
+		readonly body: MarkdownString;
 
 		/**
 		 * Optional label describing the [Comment](#Comment)
 		 * Label will be rendered next to userName if exists.
 		 */
-		label?: string;
+		readonly label?: string;
 
 		/**
 		 * The display name of the user who created the comment
 		 */
-		userName: string;
+		readonly userName: string;
 
 		/**
 		 * The icon path for the user who created the comment
 		 */
-		userIconPath?: Uri;
+		readonly userIconPath?: Uri;
 
 		/**
 		 * The command to be executed if the comment is selected in the Comments Panel
 		 */
-		selectCommand?: Command;
+		readonly selectCommand?: Command;
 
 		/**
 		 * The command to be executed when users try to save the edits to the comment
 		 */
-		editCommand?: Command;
+		readonly editCommand?: Command;
 
 		/**
 		 * The command to be executed when users try to delete the comment
 		 */
-		deleteCommand?: Command;
+		readonly deleteCommand?: Command;
 	}