diff --git a/src/vaadin-context-menu.html b/src/vaadin-context-menu.html
index f8ba6856..63c6cceb 100644
--- a/src/vaadin-context-menu.html
+++ b/src/vaadin-context-menu.html
@@ -296,6 +296,7 @@
 
             /**
              * Event name to listen for opening the context menu.
+             * @attr {string} open-on
              * @type {string}
              */
             openOn: {
@@ -319,6 +320,7 @@
 
             /**
              * Event name to listen for closing the context menu.
+             * @attr {string} close-on
              * @type {string}
              */
             closeOn: {