Hide empty Filters section in activity options menu

- Extract visibility logic into reusable hook `useActivityScopeFilterMenuItemsVisible` to avoid duplication
- Only render Filters label and items when filters are available, preventing empty section in dropdown
- Improves UX by not showing unused menu sections

src/renderer/src/components/activity/activity-scope-filter-controls.tsx

@@ -10,6 +10,24 @@ import {
 } from '@/components/sidebar/sidebar-host-options'
 import { useSidebarHostScopeOptions } from '@/components/sidebar/use-sidebar-host-scope-options'
 
+/**
+ * Whether {@link ActivityScopeFilterMenuItems} renders anything.
+ * Why exported: the parent owns the Filters label and separator, so it has to
+ * know whether the section would be empty.
+ */
+export function useActivityScopeFilterMenuItemsVisible(): boolean {
+  const repos = useAppStore((s) => s.repos)
+  const agentsVisibleHostIds = useAppStore((s) => s.agentsVisibleHostIds)
+  const agentsFilterRepoIds = useAppStore((s) => s.agentsFilterRepoIds)
+  const { hostOptions } = useSidebarHostScopeOptions()
+  return (
+    agentsVisibleHostIds !== null ||
+    agentsFilterRepoIds.length > 0 ||
+    shouldShowHostScopeControls(hostOptions) ||
+    repos.length > 1
+  )
+}
+
 /**
  * Host/project scope items for the Agents activity surfaces. State is the
  * persisted agents-view scope (agentsVisibleHostIds / agentsFilterRepoIds),
@@ -17,7 +35,6 @@ import { useSidebarHostScopeOptions } from '@/components/sidebar/use-sidebar-hos
  * Filters label and separator.
  */
 export function ActivityScopeFilterMenuItems(): React.JSX.Element | null {
-  const repos = useAppStore((s) => s.repos)
   const agentsVisibleHostIds = useAppStore((s) => s.agentsVisibleHostIds)
   const setAgentsVisibleHostIds = useAppStore((s) => s.setAgentsVisibleHostIds)
   const agentsFilterRepoIds = useAppStore((s) => s.agentsFilterRepoIds)
@@ -25,8 +42,9 @@ export function ActivityScopeFilterMenuItems(): React.JSX.Element | null {
   const { hostOptions } = useSidebarHostScopeOptions()
   const showHostScopeControls = shouldShowHostScopeControls(hostOptions)
   const hasScopeFilter = agentsVisibleHostIds !== null || agentsFilterRepoIds.length > 0
+  const visible = useActivityScopeFilterMenuItemsVisible()
 
-  if (!hasScopeFilter && !showHostScopeControls && repos.length <= 1) {
+  if (!visible) {
     return null
   }
 

src/renderer/src/components/activity/activity-thread-options-menu.tsx

@@ -19,7 +19,8 @@ import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip
 import { translate } from '@/i18n/i18n'
 import {
   ActivityScopeFilterMenuItems,
-  useActivityScopeFilterActive
+  useActivityScopeFilterActive,
+  useActivityScopeFilterMenuItemsVisible
 } from './activity-scope-filter-controls'
 import type { ActivityGroupBy } from './activity-thread-types'
 
@@ -79,6 +80,10 @@ export function ActivityThreadOptionsMenu({
 }): React.JSX.Element {
   const skipCloseAutoFocusRef = React.useRef(false)
   const scopeFilterActive = useActivityScopeFilterActive()
+  const scopeFilterItemsVisible = useActivityScopeFilterMenuItemsVisible()
+  const hasFilters = Boolean(
+    onUnreadOnlyChange || onShowChildAgentsChange || scopeFilterItemsVisible
+  )
   const optionsLabel = scopeFilterActive
     ? translate(
         'auto.components.activity.ActivityPrototypePage.threadListOptionsFiltered',
@@ -131,35 +136,42 @@ export function ActivityThreadOptionsMenu({
           }
         }}
       >
-        <DropdownMenuLabel>
-          {translate('auto.components.activity.ActivityPrototypePage.filtersSection', 'Filters')}
-        </DropdownMenuLabel>
-        {onUnreadOnlyChange ? (
-          <DropdownMenuCheckboxItem
-            checked={unreadOnly}
-            onCheckedChange={(checked) => onUnreadOnlyChange(checked === true)}
-            onSelect={(event) => event.preventDefault()}
-          >
-            {translate(
-              'auto.components.activity.ActivityPrototypePage.showUnreadOnly',
-              'Show unread only'
-            )}
-          </DropdownMenuCheckboxItem>
+        {hasFilters ? (
+          <>
+            <DropdownMenuLabel>
+              {translate(
+                'auto.components.activity.ActivityPrototypePage.filtersSection',
+                'Filters'
+              )}
+            </DropdownMenuLabel>
+            {onUnreadOnlyChange ? (
+              <DropdownMenuCheckboxItem
+                checked={unreadOnly}
+                onCheckedChange={(checked) => onUnreadOnlyChange(checked === true)}
+                onSelect={(event) => event.preventDefault()}
+              >
+                {translate(
+                  'auto.components.activity.ActivityPrototypePage.showUnreadOnly',
+                  'Show unread only'
+                )}
+              </DropdownMenuCheckboxItem>
+            ) : null}
+            {onShowChildAgentsChange ? (
+              <DropdownMenuCheckboxItem
+                checked={showChildAgents}
+                onCheckedChange={(checked) => onShowChildAgentsChange(checked === true)}
+                onSelect={(event) => event.preventDefault()}
+              >
+                {translate(
+                  'auto.components.activity.ActivityPrototypePage.showChildAgents',
+                  'Show child agents'
+                )}
+              </DropdownMenuCheckboxItem>
+            ) : null}
+            <ActivityScopeFilterMenuItems />
+            <DropdownMenuSeparator />
+          </>
         ) : null}
-        {onShowChildAgentsChange ? (
-          <DropdownMenuCheckboxItem
-            checked={showChildAgents}
-            onCheckedChange={(checked) => onShowChildAgentsChange(checked === true)}
-            onSelect={(event) => event.preventDefault()}
-          >
-            {translate(
-              'auto.components.activity.ActivityPrototypePage.showChildAgents',
-              'Show child agents'
-            )}
-          </DropdownMenuCheckboxItem>
-        ) : null}
-        <ActivityScopeFilterMenuItems />
-        <DropdownMenuSeparator />
         <DropdownMenuLabel>
           {translate('auto.components.activity.ActivityPrototypePage.viewSection', 'View')}
         </DropdownMenuLabel>