diff --git a/packages/cli/src/ui/components/AuthDialog.tsx b/packages/cli/src/ui/components/AuthDialog.tsx
index 1a7c73a3..4984a1c9 100644
--- a/packages/cli/src/ui/components/AuthDialog.tsx
+++ b/packages/cli/src/ui/components/AuthDialog.tsx
@@ -47,7 +47,7 @@ export function AuthDialog({
   const [showOpenAIKeyPrompt, setShowOpenAIKeyPrompt] = useState(false);
   const items = [{ label: 'OpenAI', value: AuthType.USE_OPENAI }];
 
-  const initialAuthIndex = items.findIndex((item) => {
+  const initialAuthIndex = Math.max(0, items.findIndex((item) => {
     if (settings.merged.selectedAuthType) {
       return item.value === settings.merged.selectedAuthType;
     }
@@ -64,7 +64,7 @@ export function AuthDialog({
     }
 
     return item.value === AuthType.LOGIN_WITH_GOOGLE;
-  });
+  }));
 
   const handleAuthSelect = (authMethod: AuthType) => {
     const error = validateAuthMethod(authMethod);
diff --git a/packages/cli/src/ui/components/shared/RadioButtonSelect.tsx b/packages/cli/src/ui/components/shared/RadioButtonSelect.tsx
index 499c136a..53bf29fa 100644
--- a/packages/cli/src/ui/components/shared/RadioButtonSelect.tsx
+++ b/packages/cli/src/ui/components/shared/RadioButtonSelect.tsx
@@ -59,6 +59,15 @@ export function RadioButtonSelect<T>({
   const [activeIndex, setActiveIndex] = useState(initialIndex);
   const [scrollOffset, setScrollOffset] = useState(0);
 
+  // Ensure activeIndex is always within bounds when items change
+  useEffect(() => {
+    if (items.length === 0) {
+      setActiveIndex(0);
+    } else if (activeIndex >= items.length) {
+      setActiveIndex(Math.max(0, items.length - 1));
+    }
+  }, [items.length, activeIndex]);
+
   useEffect(() => {
     const newScrollOffset = Math.max(
       0,
@@ -74,17 +83,28 @@ export function RadioButtonSelect<T>({
   useInput(
     (input, key) => {
       if (input === 'k' || key.upArrow) {
-        const newIndex = activeIndex > 0 ? activeIndex - 1 : items.length - 1;
-        setActiveIndex(newIndex);
-        onHighlight?.(items[newIndex]!.value);
+        if (items.length > 0) {
+          const newIndex = activeIndex > 0 ? activeIndex - 1 : items.length - 1;
+          setActiveIndex(newIndex);
+          if (items[newIndex]) {
+            onHighlight?.(items[newIndex].value);
+          }
+        }
       }
       if (input === 'j' || key.downArrow) {
-        const newIndex = activeIndex < items.length - 1 ? activeIndex + 1 : 0;
-        setActiveIndex(newIndex);
-        onHighlight?.(items[newIndex]!.value);
+        if (items.length > 0) {
+          const newIndex = activeIndex < items.length - 1 ? activeIndex + 1 : 0;
+          setActiveIndex(newIndex);
+          if (items[newIndex]) {
+            onHighlight?.(items[newIndex].value);
+          }
+        }
       }
       if (key.return) {
-        onSelect(items[activeIndex]!.value);
+        // Add bounds check before accessing items[activeIndex]
+        if (activeIndex >= 0 && activeIndex < items.length && items[activeIndex]) {
+          onSelect(items[activeIndex].value);
+        }
       }
 
       // Enable selection directly from number keys.
@@ -98,7 +118,7 @@ export function RadioButtonSelect<T>({
         }
       }
     },
-    { isActive: isFocused && items.length > 0 },
+    { isActive: isFocused && items.length > 0 && activeIndex >= 0 && activeIndex < items.length },
   );
 
   const visibleItems = items.slice(scrollOffset, scrollOffset + maxItemsToShow);