diff --git a/web/app/shared/services/scalar/scalar-widget.api.ts b/web/app/shared/services/scalar/scalar-widget.api.ts
index 3267145..5897344 100644
--- a/web/app/shared/services/scalar/scalar-widget.api.ts
+++ b/web/app/shared/services/scalar/scalar-widget.api.ts
@@ -88,6 +88,10 @@ export class ScalarWidgetApi {
         ScalarWidgetApi.callAction("get_openid", {});
     }
 
+    public static requestSupportedVersions(): void {
+        ScalarWidgetApi.callAction("supported_api_versions", {});
+    }
+
     private static callAction(action, payload) {
         if (!window.opener) {
             return;
diff --git a/web/app/widget-wrappers/reauth-example/reauth-example.component.ts b/web/app/widget-wrappers/reauth-example/reauth-example.component.ts
index dcdd98d..2a9851f 100644
--- a/web/app/widget-wrappers/reauth-example/reauth-example.component.ts
+++ b/web/app/widget-wrappers/reauth-example/reauth-example.component.ts
@@ -14,12 +14,12 @@ import { FE_ScalarOpenIdRequestBody } from "../../shared/models/scalar-server-re
 })
 export class ReauthExampleWidgetWrapperComponent extends CapableWidget implements OnInit, OnDestroy {
 
-    public busy = false;
+    public busy = true; // busy until we load supported versions
     public hasOpenId = false;
     public userId: string;
     public blocked = false;
     public error = false;
-    public stateMessage = "";
+    public stateMessage = "Checking client version...";
 
     private widgetReplySubscription: Subscription;
     private widgetRequestSubscription: Subscription;
@@ -38,14 +38,30 @@ export class ReauthExampleWidgetWrapperComponent extends CapableWidget implement
     }
 
     public ngOnInit(): void {
-        // TODO: Check that the client supports this (API version 0.0.2 at least)
-
         super.ngOnInit();
         this.widgetReplySubscription = ScalarWidgetApi.replyReceived.subscribe(async response => {
-            if (response.action !== "get_openid") return;
-
             const data = response.response;
 
+            if (response.action === "supported_api_versions") {
+                if (!data || !data.supported_versions) {
+                    this.stateMessage = "Invalid API version response";
+                    this.changeDetector.detectChanges();
+                    return;
+                }
+
+                if (data.supported_versions.indexOf("0.0.2") === -1) {
+                    this.stateMessage = "Your client is not supported by this widget.";
+                    this.changeDetector.detectChanges();
+                    return;
+                }
+
+                this.busy = false;
+                this.changeDetector.detectChanges();
+                return;
+            }
+
+            if (response.action !== "get_openid") return;
+
             try {
                 if (data.state === "request") {
                     this.stateMessage = "Waiting for you to accept the prompt...";
@@ -96,6 +112,13 @@ export class ReauthExampleWidgetWrapperComponent extends CapableWidget implement
         if (this.widgetRequestSubscription) this.widgetRequestSubscription.unsubscribe();
     }
 
+    protected onCapabilitiesSent(): void {
+        super.onCapabilitiesSent();
+
+        // Start a request for supported API versions
+        ScalarWidgetApi.requestSupportedVersions();
+    }
+
     public onReauthStart(): void {
         this.busy = true;
         this.error = false;