diff --git a/client/coral-framework/services/postMessage.js b/client/coral-framework/services/postMessage.js
index bf4a11305..f3da0750c 100644
--- a/client/coral-framework/services/postMessage.js
+++ b/client/coral-framework/services/postMessage.js
@@ -6,7 +6,8 @@ import remove from 'lodash/remove';
 /**
  * createPostMessage returns a service that deals with cross
  * window communication using the postMessage API.
- * @param  {Object}  options
+ * @param  {string}  origin
+ * @param  {string}  scope
  * @return {Object}  messenger service
  */
 export function createPostMessage(origin, scope = 'client') {