diff --git a/packages/extension-collaboration/src/collaboration.ts b/packages/extension-collaboration/src/collaboration.ts
index a48ac60e4..59d3378af 100644
--- a/packages/extension-collaboration/src/collaboration.ts
+++ b/packages/extension-collaboration/src/collaboration.ts
@@ -11,6 +11,9 @@ export interface CollaborationOptions {
    * An initialized Y.js document.
    */
   document: any,
+  /**
+   * A string to determine the fragment that should be used.
+   */
   fragment: string,
 }