diff --git a/client/src/hooks/useMediaAnnotations.js b/client/src/hooks/useMediaAnnotations.js
index 9484e44e20..3f923a389a 100644
--- a/client/src/hooks/useMediaAnnotations.js
+++ b/client/src/hooks/useMediaAnnotations.js
@@ -77,7 +77,7 @@ export function useMediaAnnotations() {
     return () => socket.off('media:annotation:updated', onUpdate);
   }, []);
 
-  const updateAnnotation = useCallback(async (key, patch) => {
+  const updateAnnotation = useCallback(async (key, patch, { silent = false } = {}) => {
     // Snapshot prior state synchronously from the ref — state updaters in
     // React 18 concurrent mode can be deferred or retried, so mutating an
     // outer `let prior` from inside `setAnnotations((prev) => { ... })` is
@@ -103,8 +103,10 @@ export function useMediaAnnotations() {
       else next[key] = nextEntry;
       return next;
     });
+    let failed = false;
     const res = await setMediaAnnotation(key, patch, { silent: true }).catch((err) => {
-      toast.error(err?.message || 'Failed to save annotation');
+      failed = true;
+      if (!silent) toast.error(err?.message || 'Failed to save annotation');
       setAnnotations((prev) => {
         const reverted = { ...prev };
         if (prior) reverted[key] = prior;
@@ -113,7 +115,10 @@ export function useMediaAnnotations() {
       });
       return null;
     });
-    return res?.entry ?? null;
+    // `entry` is legitimately `null` on a real success too (the server clears
+    // the entry entirely once both `starred` and `note` are empty) — `ok` is
+    // the only reliable success signal, entry alone can't disambiguate.
+    return { ok: !failed, entry: res?.entry ?? null };
   }, []);
 
   // Reads prior starred state from the ref so the callback's identity stays
diff --git a/client/src/pages/MediaCollectionDetail.jsx b/client/src/pages/MediaCollectionDetail.jsx
index 56e5465265..f8bb6bf9f5 100644
--- a/client/src/pages/MediaCollectionDetail.jsx
+++ b/client/src/pages/MediaCollectionDetail.jsx
@@ -227,11 +227,21 @@ export default function MediaCollectionDetail() {
   const bulkStar = async (starred) => {
     if (selectedItems.length === 0) return;
     setBulkBusy(true);
+    let successCount = 0;
+    let failedCount = 0;
     for (const it of selectedItems) {
-      await updateAnnotation(it.key, { starred });
+      const { ok } = await updateAnnotation(it.key, { starred }, { silent: true });
+      if (ok) successCount++; else failedCount++;
     }
     setBulkBusy(false);
-    toast.success(`${starred ? 'Favorited' : 'Unfavorited'} ${selectedItems.length} item${selectedItems.length === 1 ? '' : 's'}`);
+    const verb = starred ? 'Favorited' : 'Unfavorited';
+    if (failedCount === 0) {
+      toast.success(`${verb} ${successCount} item${successCount === 1 ? '' : 's'}`);
+    } else if (successCount === 0) {
+      toast.error(`Failed to ${starred ? 'favorite' : 'unfavorite'} items`);
+    } else {
+      toast.error(`${verb} ${successCount} item${successCount === 1 ? '' : 's'}; ${failedCount} failed`);
+    }
   };
 
   const bulkRemove = async () => {
diff --git a/client/src/pages/MediaCollectionDetail.test.jsx b/client/src/pages/MediaCollectionDetail.test.jsx
index 58b6c45b05..2875abe844 100644
--- a/client/src/pages/MediaCollectionDetail.test.jsx
+++ b/client/src/pages/MediaCollectionDetail.test.jsx
@@ -32,11 +32,13 @@ vi.mock('../components/ui/Toast', () => ({
   }),
 }));
 
+const mockUpdateAnnotation = vi.fn();
+
 vi.mock('../hooks/useMediaAnnotations', () => ({
   useMediaAnnotations: () => ({
     annotations: {},
     toggleStar: vi.fn(),
-    updateAnnotation: vi.fn(),
+    updateAnnotation: (...args) => mockUpdateAnnotation(...args),
     getCardProps: () => ({}),
   }),
 }));
@@ -132,6 +134,7 @@ beforeEach(() => {
   mockListMediaCollections.mockResolvedValue([REAL_COLLECTION]);
   mockGetMediaCollection.mockResolvedValue(REAL_COLLECTION);
   mockPullMissingMetadata.mockResolvedValue({ attempted: 1, recovered: 1 });
+  mockUpdateAnnotation.mockResolvedValue({ ok: true, entry: null });
 });
 
 // ── Unsorted view tests ───────────────────────────────────────────────────────
@@ -239,3 +242,69 @@ describe('MediaCollectionDetail — regular collection view', () => {
     expect(screen.queryByRole('button', { name: /pull missing prompts/i })).toBeNull();
   });
 });
+
+// ── bulkStar (#6018): must not report false success when items fail ──────────
+
+describe('MediaCollectionDetail — bulkStar', () => {
+  const THREE_ITEM_COLLECTION = {
+    ...REAL_COLLECTION,
+    items: [
+      { kind: 'image', ref: IMAGE_A.filename, addedAt: '2024-01-02' },
+      { kind: 'image', ref: IMAGE_B.filename, addedAt: '2024-01-01' },
+      { kind: 'video', ref: VIDEO_C.id, addedAt: '2024-01-03' },
+    ],
+  };
+
+  beforeEach(() => {
+    mockGetMediaCollection.mockResolvedValue(THREE_ITEM_COLLECTION);
+  });
+
+  async function enterSelectModeAndSelectAll(user) {
+    await waitFor(() => screen.getByRole('button', { name: /^select$/i }));
+    await user.click(screen.getByRole('button', { name: /^select$/i }));
+    await user.click(screen.getByRole('button', { name: /select all/i }));
+  }
+
+  it('toasts a single success message when every item succeeds', async () => {
+    mockUpdateAnnotation.mockResolvedValue({ ok: true, entry: null });
+    const user = userEvent.setup();
+    renderReal();
+    await enterSelectModeAndSelectAll(user);
+
+    await user.click(screen.getByRole('button', { name: /^star$/i }));
+
+    await waitFor(() => expect(mockUpdateAnnotation).toHaveBeenCalledTimes(3));
+    expect(mockUpdateAnnotation.mock.calls.every(([, , opts]) => opts?.silent === true)).toBe(true);
+    expect(toast.success).toHaveBeenCalledWith('Favorited 3 items');
+    expect(toast.error).not.toHaveBeenCalled();
+  });
+
+  it('toasts a single failure message with no success toast when every item fails', async () => {
+    mockUpdateAnnotation.mockResolvedValue({ ok: false, entry: null });
+    const user = userEvent.setup();
+    renderReal();
+    await enterSelectModeAndSelectAll(user);
+
+    await user.click(screen.getByRole('button', { name: /^star$/i }));
+
+    await waitFor(() => expect(mockUpdateAnnotation).toHaveBeenCalledTimes(3));
+    expect(toast.error).toHaveBeenCalledWith('Failed to favorite items');
+    expect(toast.success).not.toHaveBeenCalled();
+  });
+
+  it('toasts a single consolidated message on partial failure (no contradictory success toast)', async () => {
+    mockUpdateAnnotation
+      .mockResolvedValueOnce({ ok: true, entry: null })
+      .mockResolvedValueOnce({ ok: false, entry: null })
+      .mockResolvedValueOnce({ ok: true, entry: null });
+    const user = userEvent.setup();
+    renderReal();
+    await enterSelectModeAndSelectAll(user);
+
+    await user.click(screen.getByRole('button', { name: /^star$/i }));
+
+    await waitFor(() => expect(mockUpdateAnnotation).toHaveBeenCalledTimes(3));
+    expect(toast.error).toHaveBeenCalledWith('Favorited 2 items; 1 failed');
+    expect(toast.success).not.toHaveBeenCalled();
+  });
+});