diff --git a/apps/web/src/components/chat/TraitsPicker.tsx b/apps/web/src/components/chat/TraitsPicker.tsx
index 6593acd8e1f..8462757700e 100644
--- a/apps/web/src/components/chat/TraitsPicker.tsx
+++ b/apps/web/src/components/chat/TraitsPicker.tsx
@@ -323,6 +323,9 @@ export const TraitsMenuContent = memo(function TraitsMenuContentImpl({
                     key={option.id}
                     value={option.id}
                     hideIndicator
+                    // Base UI keeps radio menus open by default. Close on pick so
+                    // the traits menu behaves like the model picker.
+                    closeOnClick
                     disabled={ultrathinkInBodyText && descriptor.id === primarySelectDescriptor?.id}
                   >
                     <span className="flex w-full min-w-0 items-center justify-between gap-3">
@@ -362,7 +365,7 @@ export const TraitsMenuContent = memo(function TraitsMenuContentImpl({
                 }}
               >
                 {(["on", "off"] as const).map((value) => (
-                  <MenuRadioItem key={value} value={value} hideIndicator>
+                  <MenuRadioItem key={value} value={value} hideIndicator closeOnClick>
                     <span className="flex w-full min-w-0 items-center justify-between gap-3">
                       <span>{value === "on" ? "On" : "Off"}</span>
                     </span>