diff --git a/firebase-externs/firebase-app-check-externs.js b/firebase-externs/firebase-app-check-externs.js
index 92fede2f..ef51fbc9 100644
--- a/firebase-externs/firebase-app-check-externs.js
+++ b/firebase-externs/firebase-app-check-externs.js
@@ -33,7 +33,7 @@ firebase.appCheck = function (app) {};
 firebase.appCheck.AppCheck = function () {};
 
 /**
- * @param {firebase.appCheck.ReCaptchaEnterpriseProvider} provider
+ * @param {firebase.appCheck.Provider} provider
  * @param {boolean} refresh
  */
 firebase.appCheck.AppCheck.prototype.activate = function (provider, refresh) {};
@@ -41,4 +41,4 @@ firebase.appCheck.AppCheck.prototype.activate = function (provider, refresh) {};
 /**
  * @constructor
  */
-firebase.appCheck.ReCaptchaEnterpriseProvider = function (appCheckToken) {};
+firebase.appCheck.Provider = function (appCheckToken) {};
diff --git a/javascript/widgets/authui.js b/javascript/widgets/authui.js
index a9230d91..47069653 100644
--- a/javascript/widgets/authui.js
+++ b/javascript/widgets/authui.js
@@ -99,10 +99,10 @@ goog.requireType('firebaseui.auth.ui.page.Base');
 /**
  * @param {!firebase.auth.Auth} auth The Firebase Auth instance.
  * @param {string=} opt_appId The optional app id.
- * @param {string=} appCheckToken The optional app id.
+ * @param {firebase.appCheck.Provider=} appCheckProvider The optional app check provider.
  * @constructor @struct
  */
-firebaseui.auth.AuthUI = function(auth, opt_appId, appCheckToken) {
+firebaseui.auth.AuthUI = function(auth, opt_appId, appCheckProvider) {
   /** @private {boolean} Whether the current instance is deleted. */
   this.deleted_ = false;
   // Check if an instance with the same key exists. If so, throw an error,
@@ -128,12 +128,10 @@ firebaseui.auth.AuthUI = function(auth, opt_appId, appCheckToken) {
   var tempApp = firebase.initializeApp({
     ...auth['app']['options']
   }, auth['app']['name'] + firebaseui.auth.AuthUI.TEMP_APP_NAME_SUFFIX_);
-  if (appCheckToken) {
+  if (appCheckProvider) {
     const appCheck = firebase.appCheck(tempApp);
     appCheck.activate(
-        new firebase.appCheck.ReCaptchaEnterpriseProvider(
-            appCheckToken
-        ),
+        appCheckProvider,
         true // Set to true to allow auto-refresh.
     );
   }