diff --git a/web/src/components/AssistantChat/HappyComposer.tsx b/web/src/components/AssistantChat/HappyComposer.tsx
index 6982123a..4ee6b10c 100644
--- a/web/src/components/AssistantChat/HappyComposer.tsx
+++ b/web/src/components/AssistantChat/HappyComposer.tsx
@@ -59,8 +59,8 @@ export function HappyComposer(props: {
 }) {
     const {
         disabled = false,
-        permissionMode = 'default',
-        modelMode = 'default',
+        permissionMode: rawPermissionMode,
+        modelMode: rawModelMode,
         active = true,
         thinking = false,
         agentState,
@@ -73,6 +73,10 @@ export function HappyComposer(props: {
         autocompleteSuggestions = defaultSuggestionHandler
     } = props
 
+    // Use ?? to handle both null and undefined (destructuring defaults only work for undefined)
+    const permissionMode = rawPermissionMode ?? 'default'
+    const modelMode = rawModelMode ?? 'default'
+
     const api = useAssistantApi()
     const composerText = useAssistantState(({ composer }) => composer.text)
     const threadIsRunning = useAssistantState(({ thread }) => thread.isRunning)