diff --git a/googleApps.ml b/googleApps.ml
index 960cea9..17d0181 100644
--- a/googleApps.ml
+++ b/googleApps.ml
@@ -102,7 +102,7 @@ include ([%js] : sig
              type menu
              val show_sidebar : t -> HtmlOutput.t -> unit [@@js.call]
              val create_menu : t -> caption:string -> Menu.t [@@js.call]
-
+             val alert : t -> string -> unit [@@js.call]
            end
 
            module Sheet : sig
diff --git a/googleApps.mli b/googleApps.mli
index 1cf15f7..81a1b65 100644
--- a/googleApps.mli
+++ b/googleApps.mli
@@ -135,6 +135,7 @@ module Ui :
     type menu
     val show_sidebar : t -> HtmlOutput.t -> unit
     val create_menu : t -> caption:string -> Menu.t
+    val alert : t -> string -> unit
   end
 
 (** Access and modify spreadsheet sheets. *)