apps/mail/components/mail/mail.tsx (1)

189-208: toast.promise options: finally is not a recognised key

sonner’s toast.promise accepts loading, success, and error.
The cleanup logic in finally will be ignored. Call .finally on the promise instead:

-toast.promise(EnableBrain(), {
-  loading: 'Enabling autolabeling...',
-  success: 'Autolabeling enabled successfully',
-  error: 'Failed to enable autolabeling',
-  finally: async () => {
-    await refetchBrainState();
-  },
-});
+toast.promise(
+  EnableBrain().finally(refetchBrainState),
+  {
+    loading: 'Enabling autolabeling...',
+    success: 'Autolabeling enabled successfully',
+    error: 'Failed to enable autolabeling',
+  },
+);

Repeat for the Disable branch below.

apps/mail/config/navigation.ts (1)

175-179: Missing id field for new nav item

Every other primary nav item owns an id (e.g. labels, inbox). Down-stream components occasionally rely on that identifier for selection logic. Add one now to stay consistent.

 {
-  title: 'navigation.settings.categories',
+  id: 'categories',
+  title: 'navigation.settings.categories',
   url: '/settings/categories',
   icon: Tabs,
 },

apps/mail/app/(routes)/settings/categories/page.tsx (3)

68-77: Inefficient merge – leverage existing hook

useCategorySettings already implements merge + sort.
Replacing this manual useEffect keeps behaviour in one place and reduces cognitive load.

-const [categories, setCategories] = useState<CategorySetting[]>([]);
-...
-useEffect(() => { ... });
+const { categories, setCategories } = useCategorySettings(); // expose setter in hook

---

80-83: Typing: avoid any

value is typed as any which defeats type-safety.

-const handleFieldChange = (id: string, field: keyof CategorySetting, value: any) => {
+const handleFieldChange = <K extends keyof CategorySetting>(
+  id: string,
+  field: K,
+  value: CategorySetting[K],
+) => {

---

110-118: Hard-coded strings bypass i18n

Titles/labels should use the locale JSON keys to stay translatable (SettingsCard title, button text, validation toast).

apps/mail/hooks/use-categories.ts (1)

80-84: Multiple defaults not handled / re-computing constant data

1. If two categories have isDefault: true, find returns the first and silently keeps the second – worth asserting or warning.
2. defaultCategories is recreated on every render; hoist it outside the hook (file-scope) to avoid needless allocations.

apps/mail/components/mail/mail.tsx (2)

825-875: Heavy switch-statement & translation helper need tightening

1. The big switch duplicates a lot of boiler-plate. A static map reduces noise and eases future maintenance.
2. cat.id.toLowerCase().replace(' ', '') only removes the first space; use /\s+/g to handle any whitespace.

Example refactor:

const ICON_MAP: Record<string, JSX.Element> = {
  Important: <Lightning … />,
  'All Mail': <Mail … />,
  Personal: <User … />,
  Promotions: <Tag … />,
  Updates: <Bell … />,
  Unread: <ScanEye … />,
};

const categories = categorySettings.map((cat) => ({
  ...cat,
  name: cat.name || t(`common.mailCategories.${cat.id.toLowerCase().replace(/\s+/g, '')}` as any),
  icon: ICON_MAP[cat.id],
}));

This also gracefully leaves icon undefined for unknown categories without casting to any.

---

909-912: Redundant second default lookup

useDefaultCategoryId() is already executed in MailLayout. Re-computing inside every CategorySelect mount adds extra work. Consider lifting the hook up and passing the defaultCategoryId as a prop to avoid duplicate memoisation.

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

apps/mail/hooks/use-categories.ts (2)

6-12: id union blocks future custom categories
Previous review still applies – constraining id to six literals prevents user-defined categories that the settings UI implicitly allows.
Change to string (or a branded string) to stay forward-compatible.

---

24-38: Custom (non-default) categories are silently dropped
The merge only iterates over defaultCategories, so a user-added category that isn’t in the defaults disappears at runtime.
See prior suggestion to include overrides.filter(o => !defaultCategories.some(d => d.id === o.id)).

apps/server/src/lib/prompts.ts (1)

264-274: Consider deduplicating the category-mapping block

The Gmail and Outlook prompts now embed identical (but soon to diverge) XML for default categories.
Extract a single TS constant (e.g., DEFAULT_CATEGORY_MAPPINGS_XML) and interpolate it into each prompt to avoid manual drift when the list is updated or localized.

apps/mail/app/(routes)/settings/categories/page.tsx (2)

120-128: Switch can still leave zero defaults in component state

Turning off the only default sets every category’s isDefault to false, leaving an interim state that fails validation at save time.
While the toast prevents persistence, consider disallowing the toggle-off when it is the sole default, to avoid user confusion.

onCheckedChange={(val) => {
-  const newCats = categories.map((c) => ({
-    ...c,
-    isDefault: c.id === cat.id ? val : false,
-  }));
+  if (!val && cat.isDefault && categories.filter(c => c.isDefault).length === 1) {
+    // Ignore attempt to unset the last default
+    return;
+  }
+  const newCats = categories.map((c) => ({
+    ...c,
+    isDefault: c.id === cat.id ? val : false,
+  }));
   setCategories(newCats);
}}

---

229-238: Number() accepts hex & scientific notation – prefer parseInt

When parsing the order value, Number('0x10') ⇒ 16 and Number('1e3') ⇒ 1000, which are unlikely to be intended.
parseInt(val, 10) avoids these surprises.

-const parsed = val === '' ? undefined : Number(val);
+const parsed = val === '' ? undefined : parseInt(val, 10);

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

apps/mail/app/(routes)/settings/shortcuts/page.tsx (1)

74-80: Untranslated hard-coded “Show ” prefix + potential undefined access

1. label = \Show ${cat.name}`bakes English into the UI. Use i18n, e.g. label = t('pages.settings.shortcuts.showLabel', { name: cat.name })`.

2. The guard categorySettings.length is fine only if the hook always returns an array.
   If it can be undefined during loading, categorySettings.length will throw.
   Either default the hook to [] or change the check to categorySettings?.length.

apps/mail/lib/hotkeys/mail-list-hotkeys.tsx (1)

222-228: Duplicate mapping logic – extract to a shared utility

The same hard-coded index mapping now lives here and in settings/shortcuts/page.tsx. Divergence is likely over time. Export one shared helper (e.g. getCategoryIdForAction(action: 'showImportant' | …)) from use-categories.ts and import it in both places.

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro