diff --git a/client/src/components/SidePanel/Agents/Version/VersionItem.tsx b/client/src/components/SidePanel/Agents/Version/VersionItem.tsx
index 1e36ef706a..407860caa8 100644
--- a/client/src/components/SidePanel/Agents/Version/VersionItem.tsx
+++ b/client/src/components/SidePanel/Agents/Version/VersionItem.tsx
@@ -53,11 +53,12 @@ export default function VersionItem({
   const date = getTimestampDate(version);
   const hasUpdatedAt = version.updatedAt != null;
   const hasCreatedAt = version.createdAt != null;
-  const relativeLabel = date
-    ? formatDistanceToNow(date, { addSuffix: true })
-    : hasUpdatedAt || hasCreatedAt
-      ? localize('com_ui_agent_version_unknown_date')
-      : localize('com_ui_agent_version_no_date');
+  const fallbackDateLabel = localize(
+    hasUpdatedAt || hasCreatedAt
+      ? 'com_ui_agent_version_unknown_date'
+      : 'com_ui_agent_version_no_date',
+  );
+  const relativeLabel = date ? formatDistanceToNow(date, { addSuffix: true }) : fallbackDateLabel;
   const absoluteLabel = date ? date.toLocaleString() : relativeLabel;
 
   const toolsCount = countItems(version.tools);
diff --git a/client/src/components/SidePanel/Builder/ActionsPanel.tsx b/client/src/components/SidePanel/Builder/ActionsPanel.tsx
index 9cf39a2a62..edb6837ca8 100644
--- a/client/src/components/SidePanel/Builder/ActionsPanel.tsx
+++ b/client/src/components/SidePanel/Builder/ActionsPanel.tsx
@@ -71,7 +71,7 @@ export default function ActionsPanel({
     },
   });
 
-  const { reset, watch } = methods;
+  const { reset } = methods;
 
   useEffect(() => {
     if (action?.metadata?.auth) {
diff --git a/client/src/data-provider/Favorites.ts b/client/src/data-provider/Favorites.ts
index 4bac514ab5..17b53513b5 100644
--- a/client/src/data-provider/Favorites.ts
+++ b/client/src/data-provider/Favorites.ts
@@ -62,13 +62,20 @@ export const useGetToolFavoritesQuery = (
 export const useAddToolFavoriteMutation = () => {
   const queryClient = useQueryClient();
   return useMutation((favorite: TToolFavorite) => dataService.addToolFavorite(favorite), {
+    /** Optimistic writes only apply over known server data. Before the list
+     * query has populated, seeding the cache from `[]` would make the toggled
+     * item look like the user's only favorite (and `cancelQueries` kills the
+     * initial fetch that would correct it) — so skip the write and let
+     * `onSettled` refetch the authoritative list instead. */
     onMutate: async (favorite) => {
       await queryClient.cancelQueries([QueryKeys.toolFavorites]);
       const previous = queryClient.getQueryData<TToolFavorite[]>([QueryKeys.toolFavorites]);
-      queryClient.setQueryData<TToolFavorite[]>([QueryKeys.toolFavorites], (current) => {
-        const list = current ?? [];
-        return list.some((f) => sameFavorite(f, favorite)) ? list : [...list, favorite];
-      });
+      if (previous !== undefined) {
+        queryClient.setQueryData<TToolFavorite[]>(
+          [QueryKeys.toolFavorites],
+          previous.some((f) => sameFavorite(f, favorite)) ? previous : [...previous, favorite],
+        );
+      }
       return { previous };
     },
     onError: (_err, _favorite, context) => {
@@ -76,6 +83,11 @@ export const useAddToolFavoriteMutation = () => {
         queryClient.setQueryData([QueryKeys.toolFavorites], context.previous);
       }
     },
+    onSettled: (_data, _err, _favorite, context) => {
+      if (context?.previous === undefined) {
+        queryClient.invalidateQueries([QueryKeys.toolFavorites]);
+      }
+    },
   });
 };
 
@@ -85,9 +97,12 @@ export const useRemoveToolFavoriteMutation = () => {
     onMutate: async (favorite) => {
       await queryClient.cancelQueries([QueryKeys.toolFavorites]);
       const previous = queryClient.getQueryData<TToolFavorite[]>([QueryKeys.toolFavorites]);
-      queryClient.setQueryData<TToolFavorite[]>([QueryKeys.toolFavorites], (current) =>
-        (current ?? []).filter((f) => !sameFavorite(f, favorite)),
-      );
+      if (previous !== undefined) {
+        queryClient.setQueryData<TToolFavorite[]>(
+          [QueryKeys.toolFavorites],
+          previous.filter((f) => !sameFavorite(f, favorite)),
+        );
+      }
       return { previous };
     },
     onError: (_err, _favorite, context) => {
@@ -95,5 +110,10 @@ export const useRemoveToolFavoriteMutation = () => {
         queryClient.setQueryData([QueryKeys.toolFavorites], context.previous);
       }
     },
+    onSettled: (_data, _err, _favorite, context) => {
+      if (context?.previous === undefined) {
+        queryClient.invalidateQueries([QueryKeys.toolFavorites]);
+      }
+    },
   });
 };
diff --git a/client/src/hooks/__tests__/useToolFavorites.spec.tsx b/client/src/hooks/__tests__/useToolFavorites.spec.tsx
index d2672bf2df..eb6ddf15ff 100644
--- a/client/src/hooks/__tests__/useToolFavorites.spec.tsx
+++ b/client/src/hooks/__tests__/useToolFavorites.spec.tsx
@@ -98,6 +98,25 @@ describe('useToolFavorites', () => {
     expect(result.current.isFavorite({ kind: 'action', id: 'a1' })).toBe(false);
   });
 
+  test('starring before the list loads refetches instead of hiding existing favorites', async () => {
+    mockGetToolFavorites
+      .mockImplementationOnce(() => new Promise<TToolFavorite[]>(() => undefined))
+      .mockResolvedValueOnce([...seeded, { itemType: 'skill', itemId: 's1' }]);
+
+    const { result } = renderHook(() => useToolFavorites(), { wrapper: createWrapper() });
+
+    await act(async () => {
+      await result.current.toggle({ kind: 'skill', id: 's1' });
+    });
+
+    await waitFor(() =>
+      expect(result.current.favoriteKeys).toEqual(
+        new Set(['tool:dalle', 'mcp:everything', 'skill:s1']),
+      ),
+    );
+    expect(mockGetToolFavorites).toHaveBeenCalledTimes(2);
+  });
+
   test('shows the item-worded cap toast and rolls back on rejection', async () => {
     mockAddToolFavorite.mockRejectedValue({
       response: { data: { code: 'MAX_FAVORITES_EXCEEDED', limit: 100 } },