diff --git a/src/components/admin/brochures-admin-panel.tsx b/src/components/admin/brochures-admin-panel.tsx
index 45847d4..bcdaec9 100644
--- a/src/components/admin/brochures-admin-panel.tsx
+++ b/src/components/admin/brochures-admin-panel.tsx
@@ -29,6 +29,7 @@ import { Label } from '@/components/ui/label';
 import { Textarea } from '@/components/ui/textarea';
 import { Switch } from '@/components/ui/switch';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface BrochureRow {
   id: string;
@@ -123,8 +124,7 @@ function BrochureCard({ brochure, onChange }: { brochure: BrochureRow; onChange:
       toast.success('Default brochure updated');
       onChange();
     },
-    onError: (e) =>
-      toast.error(e instanceof Error ? e.message : 'Could not update default brochure'),
+    onError: (e) => toastError(e),
   });
 
   const archiveMutation = useMutation({
@@ -133,7 +133,7 @@ function BrochureCard({ brochure, onChange }: { brochure: BrochureRow; onChange:
       toast.success('Brochure archived');
       onChange();
     },
-    onError: (e) => toast.error(e instanceof Error ? e.message : 'Archive failed'),
+    onError: (e) => toastError(e),
   });
 
   async function handleUpload(file: File) {
@@ -168,7 +168,7 @@ function BrochureCard({ brochure, onChange }: { brochure: BrochureRow; onChange:
       toast.success('New version uploaded');
       onChange();
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Upload failed');
+      toastError(err);
     } finally {
       setUploading(false);
     }
@@ -287,7 +287,7 @@ function CreateBrochureDialog({
       onCreated();
       onOpenChange(false);
     },
-    onError: (e) => toast.error(e instanceof Error ? e.message : 'Could not create brochure'),
+    onError: (e) => toastError(e),
   });
 
   return (
diff --git a/src/components/admin/documenso/documenso-test-button.tsx b/src/components/admin/documenso/documenso-test-button.tsx
index 6248c57..aca6db8 100644
--- a/src/components/admin/documenso/documenso-test-button.tsx
+++ b/src/components/admin/documenso/documenso-test-button.tsx
@@ -6,6 +6,7 @@ import { toast } from 'sonner';
 
 import { Button } from '@/components/ui/button';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface HealthResponse {
   ok: boolean;
@@ -35,7 +36,7 @@ export function DocumensoTestButton() {
     } catch (err) {
       const message = err instanceof Error ? err.message : 'Test failed';
       setResult({ ok: false, error: message });
-      toast.error(message);
+      toastError(err);
     } finally {
       setPending(false);
     }
diff --git a/src/components/admin/duplicates/duplicates-review-queue.tsx b/src/components/admin/duplicates/duplicates-review-queue.tsx
index bf6aeb4..c84a23a 100644
--- a/src/components/admin/duplicates/duplicates-review-queue.tsx
+++ b/src/components/admin/duplicates/duplicates-review-queue.tsx
@@ -10,6 +10,7 @@ import { PageHeader } from '@/components/shared/page-header';
 import { EmptyState } from '@/components/shared/empty-state';
 import { Skeleton } from '@/components/ui/skeleton';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { cn } from '@/lib/utils';
 
 interface CandidatePair {
@@ -104,7 +105,7 @@ function CandidateRow({
       queryClient.invalidateQueries({ queryKey: ['admin', 'duplicates'] });
       queryClient.invalidateQueries({ queryKey: ['clients'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Merge failed'),
+    onError: (err) => toastError(err),
     onSettled: () => setBusy(null),
   });
 
@@ -114,7 +115,7 @@ function CandidateRow({
       toast.message('Dismissed');
       queryClient.invalidateQueries({ queryKey: ['admin', 'duplicates'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Dismiss failed'),
+    onError: (err) => toastError(err),
     onSettled: () => setBusy(null),
   });
 
diff --git a/src/components/admin/forms/form-template-form.tsx b/src/components/admin/forms/form-template-form.tsx
index 7fbab9b..6ddf53d 100644
--- a/src/components/admin/forms/form-template-form.tsx
+++ b/src/components/admin/forms/form-template-form.tsx
@@ -19,6 +19,7 @@ import {
 } from '@/components/ui/select';
 import { Sheet, SheetContent, SheetFooter, SheetHeader, SheetTitle } from '@/components/ui/sheet';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import type { FormField } from '@/lib/validators/form-templates';
 
 interface FormTemplate {
@@ -97,7 +98,7 @@ export function FormTemplateForm({ open, onOpenChange, template, onSaved }: Prop
       onSaved();
       onOpenChange(false);
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Save failed'),
+    onError: (err) => toastError(err),
   });
 
   function updateField(idx: number, patch: Partial<FormField>) {
diff --git a/src/components/admin/forms/form-template-list.tsx b/src/components/admin/forms/form-template-list.tsx
index 444a850..190b48f 100644
--- a/src/components/admin/forms/form-template-list.tsx
+++ b/src/components/admin/forms/form-template-list.tsx
@@ -11,6 +11,7 @@ import { Button } from '@/components/ui/button';
 import { ConfirmationDialog } from '@/components/shared/confirmation-dialog';
 import { PageHeader } from '@/components/shared/page-header';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import type { FormField } from '@/lib/validators/form-templates';
 import { FormTemplateForm } from './form-template-form';
 
@@ -41,7 +42,7 @@ export function FormTemplateList() {
       toast.success('Template deleted');
       qc.invalidateQueries({ queryKey: ['admin', 'form-templates'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Delete failed'),
+    onError: (err) => toastError(err),
   });
 
   return (
diff --git a/src/components/admin/invitations/invitations-manager.tsx b/src/components/admin/invitations/invitations-manager.tsx
index d555dfb..285ad5d 100644
--- a/src/components/admin/invitations/invitations-manager.tsx
+++ b/src/components/admin/invitations/invitations-manager.tsx
@@ -12,6 +12,7 @@ import { Switch } from '@/components/ui/switch';
 import { Sheet, SheetContent, SheetFooter, SheetHeader, SheetTitle } from '@/components/ui/sheet';
 import { ConfirmationDialog } from '@/components/shared/confirmation-dialog';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface Invite {
   id: string;
@@ -56,7 +57,7 @@ export function InvitationsManager() {
       setIsSuperAdmin(false);
       qc.invalidateQueries({ queryKey: ['admin', 'invitations'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Failed to send invite'),
+    onError: (err) => toastError(err),
   });
 
   const resendMutation = useMutation({
@@ -66,7 +67,7 @@ export function InvitationsManager() {
       toast.success('Invite resent');
       qc.invalidateQueries({ queryKey: ['admin', 'invitations'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Failed to resend'),
+    onError: (err) => toastError(err),
   });
 
   const revokeMutation = useMutation({
@@ -75,7 +76,7 @@ export function InvitationsManager() {
       toast.success('Invite revoked');
       qc.invalidateQueries({ queryKey: ['admin', 'invitations'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Failed to revoke'),
+    onError: (err) => toastError(err),
   });
 
   return (
diff --git a/src/components/admin/sales-email-config-card.tsx b/src/components/admin/sales-email-config-card.tsx
index 8173374..b8d63d6 100644
--- a/src/components/admin/sales-email-config-card.tsx
+++ b/src/components/admin/sales-email-config-card.tsx
@@ -23,6 +23,7 @@ import { Label } from '@/components/ui/label';
 import { Switch } from '@/components/ui/switch';
 import { Textarea } from '@/components/ui/textarea';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface SalesConfigResponse {
   data: {
@@ -160,7 +161,7 @@ export function SalesEmailConfigCard() {
       toast.success('Sales email settings saved');
       await refresh();
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Save failed');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/admin/shared/settings-form-card.tsx b/src/components/admin/shared/settings-form-card.tsx
index f4b899a..a330fb2 100644
--- a/src/components/admin/shared/settings-form-card.tsx
+++ b/src/components/admin/shared/settings-form-card.tsx
@@ -18,6 +18,7 @@ import {
   SelectValue,
 } from '@/components/ui/select';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 export type SettingFieldType =
   | 'string'
@@ -116,7 +117,7 @@ export function SettingsFormCard({ title, description, fields, extra }: Settings
       toast.success(`Saved ${changedFields.length} setting(s)`);
       setOriginals(values);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Save failed');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/admin/storage-admin-panel.tsx b/src/components/admin/storage-admin-panel.tsx
index 49b6a61..f04cccc 100644
--- a/src/components/admin/storage-admin-panel.tsx
+++ b/src/components/admin/storage-admin-panel.tsx
@@ -17,6 +17,7 @@ import {
   DialogTitle,
 } from '@/components/ui/dialog';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 type BackendName = 's3' | 'filesystem';
 
@@ -57,8 +58,7 @@ export function StorageAdminPanel() {
       setDryRun(result.data);
       setConfirmOpen(true);
     },
-    onError: (e) =>
-      toast.error(e instanceof Error ? e.message : 'Storage migration dry-run failed'),
+    onError: (e) => toastError(e),
   });
 
   const migrateMutation = useMutation({
@@ -74,7 +74,7 @@ export function StorageAdminPanel() {
       toast.success(`Storage migration complete (${copied} file${copied === 1 ? '' : 's'} copied)`);
       queryClient.invalidateQueries({ queryKey: ['admin', 'storage', 'status'] });
     },
-    onError: (e) => toast.error(e instanceof Error ? e.message : 'Storage migration failed'),
+    onError: (e) => toastError(e),
   });
 
   const testMutation = useMutation({
diff --git a/src/components/admin/website-analytics/umami-test-button.tsx b/src/components/admin/website-analytics/umami-test-button.tsx
index f482f6f..7638bb1 100644
--- a/src/components/admin/website-analytics/umami-test-button.tsx
+++ b/src/components/admin/website-analytics/umami-test-button.tsx
@@ -6,6 +6,7 @@ import { toast } from 'sonner';
 
 import { Button } from '@/components/ui/button';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface TestResponse {
   ok: boolean;
@@ -38,7 +39,7 @@ export function UmamiTestButton() {
     } catch (err) {
       const message = err instanceof Error ? err.message : 'Test failed';
       setResult({ ok: false, error: message });
-      toast.error(message);
+      toastError(err);
     } finally {
       setPending(false);
     }
diff --git a/src/components/berths/berth-detail-header.tsx b/src/components/berths/berth-detail-header.tsx
index 4ac0c7b..514acea 100644
--- a/src/components/berths/berth-detail-header.tsx
+++ b/src/components/berths/berth-detail-header.tsx
@@ -28,6 +28,7 @@ import { DetailHeaderStrip } from '@/components/shared/detail-header-strip';
 import { PermissionGate } from '@/components/shared/permission-gate';
 import { BerthForm } from './berth-form';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { updateBerthStatusSchema, type UpdateBerthStatusInput } from '@/lib/validators/berths';
 import { BERTH_STATUSES } from '@/lib/constants';
 
@@ -123,8 +124,7 @@ function StatusChangeDialog({
       reset();
       onOpenChange(false);
     } catch (err: unknown) {
-      const message = err instanceof Error ? err.message : 'Failed to update status';
-      toast.error(message);
+      toastError(err);
     }
   }
 
diff --git a/src/components/berths/berth-documents-tab.tsx b/src/components/berths/berth-documents-tab.tsx
index 2c42177..af1facd 100644
--- a/src/components/berths/berth-documents-tab.tsx
+++ b/src/components/berths/berth-documents-tab.tsx
@@ -23,6 +23,7 @@ import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
 import { toast } from 'sonner';
 
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { Button } from '@/components/ui/button';
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
 import { Badge } from '@/components/ui/badge';
@@ -83,7 +84,7 @@ export function BerthDocumentsTab({ berthId }: { berthId: string }) {
       toast.success('Rolled back to selected version.');
     },
     onError: (err: Error) => {
-      toast.error('Rollback failed', { description: err.message });
+      toastError(err);
     },
   });
 
@@ -141,7 +142,7 @@ export function BerthDocumentsTab({ berthId }: { berthId: string }) {
       toast.success('PDF uploaded.');
     },
     onError: (err: Error) => {
-      toast.error('Upload failed', { description: err.message });
+      toastError(err);
     },
   });
 
diff --git a/src/components/berths/berth-form.tsx b/src/components/berths/berth-form.tsx
index 83483a6..853a086 100644
--- a/src/components/berths/berth-form.tsx
+++ b/src/components/berths/berth-form.tsx
@@ -21,6 +21,7 @@ import { Separator } from '@/components/ui/separator';
 import { Switch } from '@/components/ui/switch';
 import { TagPicker } from '@/components/shared/tag-picker';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { updateBerthSchema, type UpdateBerthInput } from '@/lib/validators/berths';
 import {
   BERTH_AREAS,
@@ -172,8 +173,7 @@ export function BerthForm({ berth, open, onOpenChange }: BerthFormProps) {
       toast.success('Berth updated');
       onOpenChange(false);
     } catch (err: unknown) {
-      const message = err instanceof Error ? err.message : 'Failed to update berth';
-      toast.error(message);
+      toastError(err);
     }
   }
 
diff --git a/src/components/berths/pdf-reconcile-dialog.tsx b/src/components/berths/pdf-reconcile-dialog.tsx
index a356cb9..bb5d410 100644
--- a/src/components/berths/pdf-reconcile-dialog.tsx
+++ b/src/components/berths/pdf-reconcile-dialog.tsx
@@ -21,6 +21,7 @@ import { useMutation, useQueryClient } from '@tanstack/react-query';
 import { toast } from 'sonner';
 
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { Button } from '@/components/ui/button';
 import { Checkbox } from '@/components/ui/checkbox';
 import {
@@ -93,7 +94,7 @@ export function PdfReconcileDialog({
       onClose();
     },
     onError: (err: Error) => {
-      toast.error('Apply failed', { description: err.message });
+      toastError(err);
     },
   });
 
diff --git a/src/components/clients/contacts-editor.tsx b/src/components/clients/contacts-editor.tsx
index 13e74a8..dc80348 100644
--- a/src/components/clients/contacts-editor.tsx
+++ b/src/components/clients/contacts-editor.tsx
@@ -27,6 +27,7 @@ import { InlineEditableField } from '@/components/shared/inline-editable-field';
 import { InlinePhoneField } from '@/components/shared/inline-phone-field';
 import { PhoneInput, type PhoneInputValue } from '@/components/shared/phone-input';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { cn } from '@/lib/utils';
 
 interface Contact {
@@ -161,7 +162,7 @@ function ContactRow({
     try {
       await onUpdate({ isPrimary: !contact.isPrimary });
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to update');
+      toastError(err);
     }
   }
 
@@ -170,7 +171,7 @@ function ContactRow({
     try {
       await onUpdate({ channel: next });
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to update');
+      toastError(err);
     }
   }
 
@@ -343,7 +344,7 @@ function NewContactForm({
           label: label.trim() || undefined,
         });
       } catch (err) {
-        toast.error(err instanceof Error ? err.message : 'Failed to add contact');
+        toastError(err);
       } finally {
         setSaving(false);
       }
@@ -354,7 +355,7 @@ function NewContactForm({
     try {
       await onSave({ channel, value: value.trim(), label: label.trim() || undefined });
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to add contact');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/clients/gdpr-export-button.tsx b/src/components/clients/gdpr-export-button.tsx
index b550bfe..e2f96a2 100644
--- a/src/components/clients/gdpr-export-button.tsx
+++ b/src/components/clients/gdpr-export-button.tsx
@@ -22,6 +22,7 @@ import {
 import { Badge } from '@/components/ui/badge';
 import { usePermissions } from '@/hooks/use-permissions';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface ExportRow {
   id: string;
@@ -79,7 +80,7 @@ export function GdprExportButton({ clientId }: { clientId: string }) {
       setEmailOverride('');
     },
     onError: (err: unknown) => {
-      toast.error(err instanceof Error ? err.message : 'Failed to queue export');
+      toastError(err);
     },
   });
 
@@ -92,7 +93,7 @@ export function GdprExportButton({ clientId }: { clientId: string }) {
       );
       window.open(res.data.url, '_blank', 'noopener');
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to fetch download URL');
+      toastError(err);
     }
   }
 
diff --git a/src/components/companies/company-detail-header.tsx b/src/components/companies/company-detail-header.tsx
index 228e31a..e22d1f5 100644
--- a/src/components/companies/company-detail-header.tsx
+++ b/src/components/companies/company-detail-header.tsx
@@ -13,6 +13,7 @@ import { DetailHeaderStrip } from '@/components/shared/detail-header-strip';
 import { PermissionGate } from '@/components/shared/permission-gate';
 import { CompanyForm } from '@/components/companies/company-form';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface CompanyDetailHeaderCompany {
   id: string;
@@ -66,7 +67,7 @@ export function CompanyDetailHeader({ company }: CompanyDetailHeaderProps) {
       router.push(`/${portSlug}/companies` as any);
     },
     onError: (err: Error) => {
-      toast.error(err.message || 'Failed to archive company');
+      toastError(err);
     },
   });
 
diff --git a/src/components/companies/company-members-tab.tsx b/src/components/companies/company-members-tab.tsx
index 8399481..df5d5c8 100644
--- a/src/components/companies/company-members-tab.tsx
+++ b/src/components/companies/company-members-tab.tsx
@@ -25,6 +25,7 @@ import {
 import { EmptyState } from '@/components/shared/empty-state';
 import { PermissionGate } from '@/components/shared/permission-gate';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { AddMembershipDialog } from './add-membership-dialog';
 
 interface MembershipRow {
@@ -112,7 +113,7 @@ export function CompanyMembersTab({ companyId, portSlug }: CompanyMembersTabProp
       toast.success('Membership ended');
     },
     onError: (err: Error) => {
-      toast.error(err.message || 'Failed to end membership');
+      toastError(err);
     },
   });
 
@@ -126,7 +127,7 @@ export function CompanyMembersTab({ companyId, portSlug }: CompanyMembersTabProp
       toast.success('Primary contact updated');
     },
     onError: (err: Error) => {
-      toast.error(err.message || 'Failed to set primary');
+      toastError(err);
     },
   });
 
diff --git a/src/components/documents/create-document-wizard.tsx b/src/components/documents/create-document-wizard.tsx
index cadd6ed..4581907 100644
--- a/src/components/documents/create-document-wizard.tsx
+++ b/src/components/documents/create-document-wizard.tsx
@@ -18,6 +18,7 @@ import {
 } from '@/components/ui/select';
 import { PageHeader } from '@/components/shared/page-header';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { DOCUMENT_TYPES } from '@/lib/constants';
 
 const SIGNER_ROLES = ['client', 'sales', 'approver', 'developer', 'other'] as const;
@@ -158,7 +159,7 @@ export function CreateDocumentWizard({ portSlug }: CreateDocumentWizardProps) {
       toast.success('Document created');
       router.push(`/${portSlug}/documents/${res.data.id}`);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to create document');
+      toastError(err);
       setSubmitting(false);
     }
   };
diff --git a/src/components/documents/document-detail.tsx b/src/components/documents/document-detail.tsx
index af4df7f..b30535d 100644
--- a/src/components/documents/document-detail.tsx
+++ b/src/components/documents/document-detail.tsx
@@ -13,6 +13,7 @@ import { PageHeader } from '@/components/shared/page-header';
 import { StatusPill, type StatusPillStatus } from '@/components/ui/status-pill';
 import { useRealtimeInvalidation } from '@/hooks/use-realtime-invalidation';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface DetailDoc {
   id: string;
@@ -151,7 +152,7 @@ export function DocumentDetail({ documentId, portSlug }: DocumentDetailProps) {
       toast.success('Reminder sent');
       queryClient.invalidateQueries({ queryKey: ['document-detail', documentId] });
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to send reminder');
+      toastError(err);
     }
   };
 
@@ -163,7 +164,7 @@ export function DocumentDetail({ documentId, portSlug }: DocumentDetailProps) {
       toast.success('Document cancelled');
       router.push(`/${portSlug}/documents`);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Cancel failed');
+      toastError(err);
       setIsCancelling(false);
     }
   };
@@ -177,7 +178,7 @@ export function DocumentDetail({ documentId, portSlug }: DocumentDetailProps) {
         `Email composer prepared for ${draft.data.to.length} signer${draft.data.to.length === 1 ? '' : 's'} - opens in PR8 wizard`,
       );
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to prepare email');
+      toastError(err);
     }
   };
 
@@ -357,9 +358,7 @@ export function DocumentDetail({ documentId, portSlug }: DocumentDetailProps) {
                             queryKey: ['document-detail', documentId],
                           });
                         } catch (err) {
-                          toast.error(
-                            err instanceof Error ? err.message : 'Failed to remove watcher',
-                          );
+                          toastError(err);
                         }
                       }}
                       className="text-muted-foreground hover:text-destructive"
diff --git a/src/components/email/compose-dialog.tsx b/src/components/email/compose-dialog.tsx
index 90bac32..ca04baa 100644
--- a/src/components/email/compose-dialog.tsx
+++ b/src/components/email/compose-dialog.tsx
@@ -23,6 +23,7 @@ import {
   SelectValue,
 } from '@/components/ui/select';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface Account {
   id: string;
@@ -86,7 +87,7 @@ export function ComposeDialog({
       setSubject('');
       setBody('');
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Send failed'),
+    onError: (err) => toastError(err),
   });
 
   return (
diff --git a/src/components/email/email-accounts-list.tsx b/src/components/email/email-accounts-list.tsx
index 8b14d13..8ad9967 100644
--- a/src/components/email/email-accounts-list.tsx
+++ b/src/components/email/email-accounts-list.tsx
@@ -19,6 +19,7 @@ import {
 import { Sheet, SheetContent, SheetHeader, SheetTitle, SheetFooter } from '@/components/ui/sheet';
 import { ConfirmationDialog } from '@/components/shared/confirmation-dialog';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface Account {
   id: string;
@@ -73,7 +74,7 @@ export function EmailAccountsList() {
       setSheetOpen(false);
       qc.invalidateQueries({ queryKey: ['email', 'accounts'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Failed to connect account'),
+    onError: (err) => toastError(err),
   });
 
   const toggleMutation = useMutation({
diff --git a/src/components/expenses/expense-detail.tsx b/src/components/expenses/expense-detail.tsx
index 0b9cda1..125e198 100644
--- a/src/components/expenses/expense-detail.tsx
+++ b/src/components/expenses/expense-detail.tsx
@@ -12,6 +12,7 @@ import { ArchiveConfirmDialog } from '@/components/shared/archive-confirm-dialog
 import { PermissionGate } from '@/components/shared/permission-gate';
 import { toast } from 'sonner';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { useMobileChrome } from '@/components/layout/mobile/mobile-layout-provider';
 import type { ExpenseRow } from './expense-columns';
 import { ExpenseDuplicateBanner } from './expense-duplicate-banner';
@@ -122,7 +123,7 @@ export function ExpenseDetail({ expenseId, onEdit, onArchived }: ExpenseDetailPr
       onArchived?.();
     },
     onError: (e) => {
-      toast.error(e instanceof Error ? e.message : 'Archive failed');
+      toastError(e);
       setArchiveOpen(false);
     },
   });
diff --git a/src/components/interests/inline-stage-picker.tsx b/src/components/interests/inline-stage-picker.tsx
index acfcd60..f385b86 100644
--- a/src/components/interests/inline-stage-picker.tsx
+++ b/src/components/interests/inline-stage-picker.tsx
@@ -8,6 +8,7 @@ import { toast } from 'sonner';
 import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
 import { Textarea } from '@/components/ui/textarea';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { cn } from '@/lib/utils';
 import {
   PIPELINE_STAGES,
@@ -65,7 +66,7 @@ export function InlineStagePicker({
     },
     onError: (err) => {
       setPendingStage(null);
-      toast.error(err instanceof Error ? err.message : 'Failed to change stage');
+      toastError(err);
     },
   });
 
diff --git a/src/components/invoices/invoice-detail.tsx b/src/components/invoices/invoice-detail.tsx
index cb8ee46..827f886 100644
--- a/src/components/invoices/invoice-detail.tsx
+++ b/src/components/invoices/invoice-detail.tsx
@@ -25,6 +25,7 @@ import {
 import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
 import { InvoicePdfPreview } from './invoice-pdf-preview';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { useMobileChrome } from '@/components/layout/mobile/mobile-layout-provider';
 import { recordPaymentSchema, type RecordPaymentInput } from '@/lib/validators/invoices';
 
@@ -99,7 +100,7 @@ export function InvoiceDetail({ invoiceId }: InvoiceDetailProps) {
       queryClient.invalidateQueries({ queryKey: ['invoices', invoiceId] });
       queryClient.invalidateQueries({ queryKey: ['invoices'] });
     },
-    onError: (e) => toast.error(e instanceof Error ? e.message : 'Could not send invoice'),
+    onError: (e) => toastError(e),
   });
 
   const paymentForm = useForm<RecordPaymentInput>({
@@ -118,7 +119,7 @@ export function InvoiceDetail({ invoiceId }: InvoiceDetailProps) {
       queryClient.invalidateQueries({ queryKey: ['invoices', invoiceId] });
       queryClient.invalidateQueries({ queryKey: ['invoices'] });
     },
-    onError: (e) => toast.error(e instanceof Error ? e.message : 'Could not record payment'),
+    onError: (e) => toastError(e),
   });
 
   if (isLoading) {
diff --git a/src/components/notifications/notification-preferences-form.tsx b/src/components/notifications/notification-preferences-form.tsx
index 27cdbd9..2556a69 100644
--- a/src/components/notifications/notification-preferences-form.tsx
+++ b/src/components/notifications/notification-preferences-form.tsx
@@ -7,6 +7,7 @@ import { toast } from 'sonner';
 import { Button } from '@/components/ui/button';
 import { Switch } from '@/components/ui/switch';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface Pref {
   notificationType: string;
@@ -72,7 +73,7 @@ export function NotificationPreferencesForm() {
       toast.success('Preferences saved');
       qc.invalidateQueries({ queryKey: ['notifications', 'preferences'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Save failed'),
+    onError: (err) => toastError(err),
   });
 
   function update(type: string, field: 'inApp' | 'email', value: boolean) {
diff --git a/src/components/notifications/reminder-digest-form.tsx b/src/components/notifications/reminder-digest-form.tsx
index 9a746f8..cd41777 100644
--- a/src/components/notifications/reminder-digest-form.tsx
+++ b/src/components/notifications/reminder-digest-form.tsx
@@ -17,6 +17,7 @@ import {
   SelectValue,
 } from '@/components/ui/select';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface ReminderPrefs {
   delivery: 'immediate' | 'daily' | 'weekly' | 'off';
@@ -81,7 +82,7 @@ export function ReminderDigestForm() {
       toast.success('Reminder preferences saved');
       qc.invalidateQueries({ queryKey: ['user', 'preferences'] });
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Save failed'),
+    onError: (err) => toastError(err),
   });
 
   if (isLoading) {
diff --git a/src/components/reservations/reservation-detail.tsx b/src/components/reservations/reservation-detail.tsx
index 289de3d..32e2b46 100644
--- a/src/components/reservations/reservation-detail.tsx
+++ b/src/components/reservations/reservation-detail.tsx
@@ -22,6 +22,7 @@ import { StatusPill, type StatusPillStatus } from '@/components/ui/status-pill';
 import { EmptyState } from '@/components/ui/empty-state';
 import { useRealtimeInvalidation } from '@/hooks/use-realtime-invalidation';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { ClientLink, YachtLink, BerthLink } from '@/components/reservations/reservation-list';
 
 interface ReservationDoc {
@@ -80,7 +81,7 @@ function EndReservationDialog({ reservationId, open, onOpenChange }: EndReservat
       toast.success('Reservation ended');
       onOpenChange(false);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to end reservation');
+      toastError(err);
     } finally {
       setSubmitting(false);
     }
@@ -245,7 +246,7 @@ export function ReservationDetail({ reservationId, portSlug }: ReservationDetail
                   });
                   toast.success('Reminder sent');
                 } catch (err) {
-                  toast.error(err instanceof Error ? err.message : 'Failed');
+                  toastError(err);
                 }
               }}
             >
diff --git a/src/components/residential/residential-client-detail.tsx b/src/components/residential/residential-client-detail.tsx
index beab8d2..ae2aa02 100644
--- a/src/components/residential/residential-client-detail.tsx
+++ b/src/components/residential/residential-client-detail.tsx
@@ -18,6 +18,7 @@ import { InlinePhoneField } from '@/components/shared/inline-phone-field';
 import { SubdivisionCombobox } from '@/components/shared/subdivision-combobox';
 import { useRealtimeInvalidation } from '@/hooks/use-realtime-invalidation';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import type { CountryCode } from '@/lib/i18n/countries';
 
 interface ResidentialInterestSummary {
@@ -312,7 +313,7 @@ function NewInterestSheet({
       setNotes('');
       toast.success('Interest added');
     },
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Failed to add'),
+    onError: (err) => toastError(err),
   });
 
   return (
diff --git a/src/components/residential/residential-clients-list.tsx b/src/components/residential/residential-clients-list.tsx
index 0bbc94f..2e1e3d3 100644
--- a/src/components/residential/residential-clients-list.tsx
+++ b/src/components/residential/residential-clients-list.tsx
@@ -18,6 +18,7 @@ import { SubdivisionCombobox } from '@/components/shared/subdivision-combobox';
 import { PhoneInput, type PhoneInputValue } from '@/components/shared/phone-input';
 import { useRealtimeInvalidation } from '@/hooks/use-realtime-invalidation';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { cn } from '@/lib/utils';
 import type { CountryCode } from '@/lib/i18n/countries';
 
@@ -246,7 +247,7 @@ function NewResidentialClientSheet({
       toast.success('Residential client added');
     },
     onError: (err) => {
-      toast.error(err instanceof Error ? err.message : 'Failed to create');
+      toastError(err);
     },
   });
 
diff --git a/src/components/shared/addresses-editor.tsx b/src/components/shared/addresses-editor.tsx
index 72ade65..28c83c9 100644
--- a/src/components/shared/addresses-editor.tsx
+++ b/src/components/shared/addresses-editor.tsx
@@ -11,6 +11,7 @@ import { CountryCombobox } from '@/components/shared/country-combobox';
 import { SubdivisionCombobox } from '@/components/shared/subdivision-combobox';
 import { InlineEditableField } from '@/components/shared/inline-editable-field';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import type { CountryCode } from '@/lib/i18n/countries';
 import { getCountryName } from '@/lib/i18n/countries';
 import { getSubdivisionName } from '@/lib/i18n/subdivisions';
@@ -119,7 +120,7 @@ function AddressCard({
     try {
       await onUpdate({ isPrimary: true });
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to update');
+      toastError(err);
     }
   }
 
@@ -362,7 +363,7 @@ function NewAddressForm({
         isPrimary: makePrimary,
       });
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to add address');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/shared/inline-country-field.tsx b/src/components/shared/inline-country-field.tsx
index 0894e2e..85bde21 100644
--- a/src/components/shared/inline-country-field.tsx
+++ b/src/components/shared/inline-country-field.tsx
@@ -2,9 +2,9 @@
 
 import { useRef, useState } from 'react';
 import { Loader2, Pencil } from 'lucide-react';
-import { toast } from 'sonner';
 
 import { CountryCombobox } from '@/components/shared/country-combobox';
+import { toastError } from '@/lib/api/toast-error';
 import { getCountryName, type CountryCode } from '@/lib/i18n/countries';
 import { cn } from '@/lib/utils';
 
@@ -46,7 +46,7 @@ export function InlineCountryField({
       await onSave(next);
       setEditing(false);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to save');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/shared/inline-editable-field.tsx b/src/components/shared/inline-editable-field.tsx
index 2ac7f9a..37f231a 100644
--- a/src/components/shared/inline-editable-field.tsx
+++ b/src/components/shared/inline-editable-field.tsx
@@ -2,8 +2,8 @@
 
 import { useEffect, useRef, useState } from 'react';
 import { Loader2, Pencil } from 'lucide-react';
-import { toast } from 'sonner';
 
+import { toastError } from '@/lib/api/toast-error';
 import { Input } from '@/components/ui/input';
 import { Textarea } from '@/components/ui/textarea';
 import {
@@ -85,7 +85,7 @@ export function InlineEditableField(props: InlineEditableFieldProps) {
       await onSave(trimmed === '' ? null : trimmed);
       setEditing(false);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to save');
+      toastError(err);
       setDraft(value ?? '');
     } finally {
       setSaving(false);
diff --git a/src/components/shared/inline-phone-field.tsx b/src/components/shared/inline-phone-field.tsx
index e191889..c8c126d 100644
--- a/src/components/shared/inline-phone-field.tsx
+++ b/src/components/shared/inline-phone-field.tsx
@@ -2,9 +2,9 @@
 
 import { useState } from 'react';
 import { Loader2, Pencil } from 'lucide-react';
-import { toast } from 'sonner';
 
 import { PhoneInput, type PhoneInputValue } from '@/components/shared/phone-input';
+import { toastError } from '@/lib/api/toast-error';
 import { parsePhone } from '@/lib/i18n/phone';
 import type { CountryCode } from '@/lib/i18n/countries';
 import { cn } from '@/lib/utils';
@@ -66,7 +66,7 @@ export function InlinePhoneField({
       await onSave(next);
       setEditing(false);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to save');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/shared/inline-tag-editor.tsx b/src/components/shared/inline-tag-editor.tsx
index c5ead44..a0a5f5b 100644
--- a/src/components/shared/inline-tag-editor.tsx
+++ b/src/components/shared/inline-tag-editor.tsx
@@ -3,11 +3,11 @@
 import { useState } from 'react';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { Plus, X, Check } from 'lucide-react';
-import { toast } from 'sonner';
 
 import { Button } from '@/components/ui/button';
 import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 import { cn } from '@/lib/utils';
 
 interface Tag {
@@ -45,7 +45,7 @@ export function InlineTagEditor({
   const setTags = useMutation({
     mutationFn: (tagIds: string[]) => apiFetch(endpoint, { method: 'PUT', body: { tagIds } }),
     onSuccess: () => qc.invalidateQueries({ queryKey: invalidateKey }),
-    onError: (err) => toast.error(err instanceof Error ? err.message : 'Failed to update tags'),
+    onError: (err) => toastError(err),
   });
 
   function toggleTag(tagId: string) {
diff --git a/src/components/shared/inline-timezone-field.tsx b/src/components/shared/inline-timezone-field.tsx
index a351b1b..81591dc 100644
--- a/src/components/shared/inline-timezone-field.tsx
+++ b/src/components/shared/inline-timezone-field.tsx
@@ -2,9 +2,9 @@
 
 import { useRef, useState } from 'react';
 import { Loader2, Pencil } from 'lucide-react';
-import { toast } from 'sonner';
 
 import { TimezoneCombobox } from '@/components/shared/timezone-combobox';
+import { toastError } from '@/lib/api/toast-error';
 import { formatTimezoneLabel } from '@/lib/i18n/timezones';
 import type { CountryCode } from '@/lib/i18n/countries';
 import { cn } from '@/lib/utils';
@@ -46,7 +46,7 @@ export function InlineTimezoneField({
       await onSave(next);
       setEditing(false);
     } catch (err) {
-      toast.error(err instanceof Error ? err.message : 'Failed to save');
+      toastError(err);
     } finally {
       setSaving(false);
     }
diff --git a/src/components/shared/send-document-dialog.tsx b/src/components/shared/send-document-dialog.tsx
index 6a0f70b..5a363b6 100644
--- a/src/components/shared/send-document-dialog.tsx
+++ b/src/components/shared/send-document-dialog.tsx
@@ -33,6 +33,7 @@ import { Label } from '@/components/ui/label';
 import { Textarea } from '@/components/ui/textarea';
 import { Input } from '@/components/ui/input';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 const BODY_MAX = 50_000;
 
@@ -149,7 +150,7 @@ export function SendDocumentDialog({
       }
     },
     onError: (err) => {
-      toast.error(err instanceof Error ? err.message : 'Send failed');
+      toastError(err);
     },
   });
 
diff --git a/src/components/yachts/yacht-detail-header.tsx b/src/components/yachts/yacht-detail-header.tsx
index 189956e..cc07c95 100644
--- a/src/components/yachts/yacht-detail-header.tsx
+++ b/src/components/yachts/yacht-detail-header.tsx
@@ -15,6 +15,7 @@ import { PermissionGate } from '@/components/shared/permission-gate';
 import { YachtForm } from '@/components/yachts/yacht-form';
 import { YachtTransferDialog } from '@/components/yachts/yacht-transfer-dialog';
 import { apiFetch } from '@/lib/api/client';
+import { toastError } from '@/lib/api/toast-error';
 
 interface YachtDetailHeaderYacht {
   id: string;
@@ -131,7 +132,7 @@ export function YachtDetailHeader({ yacht }: YachtDetailHeaderProps) {
       router.push(`/${portSlug}/yachts` as any);
     },
     onError: (err: Error) => {
-      toast.error(err.message || 'Failed to archive yacht');
+      toastError(err);
     },
   });
 
diff --git a/src/lib/error-codes.ts b/src/lib/error-codes.ts
index 044b045..a51bc20 100644
--- a/src/lib/error-codes.ts
+++ b/src/lib/error-codes.ts
@@ -207,6 +207,55 @@ export const ERROR_CODES = {
     status: 403,
     userMessage: 'This request was rejected by the security check.',
   },
+
+  // ─── Upstream integrations ──────────────────────────────────────────
+  DOCUMENSO_UPSTREAM_ERROR: {
+    status: 502,
+    userMessage:
+      "The signing service didn't respond as expected. Please retry, and if it keeps happening, ping an admin.",
+    hint: 'Documenso returned a non-2xx; check Documenso health + auth.',
+  },
+  DOCUMENSO_AUTH_FAILURE: {
+    status: 502,
+    userMessage:
+      'The signing service rejected our request. An admin will need to refresh the API key.',
+    hint: 'Documenso 401/403 — API key likely revoked or rotated.',
+  },
+  DOCUMENSO_TIMEOUT: {
+    status: 504,
+    userMessage: 'The signing service is taking too long to respond. Please try again in a moment.',
+  },
+  OCR_UPSTREAM_ERROR: {
+    status: 502,
+    userMessage:
+      "The receipt scanner didn't respond as expected. Please retry, or fill the fields manually.",
+  },
+  IMAP_UPSTREAM_ERROR: {
+    status: 502,
+    userMessage:
+      "We couldn't fetch your inbox just now. Please retry, and check your IMAP credentials if it persists.",
+  },
+  UMAMI_UPSTREAM_ERROR: {
+    status: 502,
+    userMessage: "Analytics data isn't available right now. Please try again shortly.",
+  },
+  UMAMI_NOT_CONFIGURED: {
+    status: 409,
+    userMessage:
+      'Analytics has not been configured for this port. Ask an admin to set up the integration.',
+  },
+
+  // ─── Internal post-insert guards ────────────────────────────────────
+  // Surfaced as a generic "something went wrong" toast because the cause
+  // is always a programmer / DB-state issue (returning row absent after a
+  // successful insert, etc.) — the rep can't action it but support can,
+  // via the request-id lookup. Use only with `internalMessage`.
+  INSERT_RETURNING_EMPTY: {
+    status: 500,
+    userMessage:
+      'Something went wrong on our end. Please try again, and quote the error ID below if it keeps happening.',
+    hint: 'A db.insert(...).returning() came back empty — DB constraint or transaction-rollback bug.',
+  },
 } as const satisfies Record<string, ErrorCodeEntry>;
 
 export type ErrorCode = keyof typeof ERROR_CODES;
diff --git a/src/lib/services/ai-budget.service.ts b/src/lib/services/ai-budget.service.ts
index cce2bf9..619bbad 100644
--- a/src/lib/services/ai-budget.service.ts
+++ b/src/lib/services/ai-budget.service.ts
@@ -15,6 +15,7 @@ import { and, eq, gte, sql } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { aiUsageLedger } from '@/lib/db/schema/ai-usage';
 import { systemSettings } from '@/lib/db/schema/system';
+import { ValidationError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 
 export type BudgetPeriod = 'day' | 'week' | 'month';
@@ -70,10 +71,10 @@ export async function setAiBudget(
     period: input.period ?? existing.period,
   };
   if (next.softCapTokens < 0 || next.hardCapTokens < 0) {
-    throw new Error('Token caps must be non-negative');
+    throw new ValidationError('Token caps must be non-negative');
   }
   if (next.softCapTokens > next.hardCapTokens) {
-    throw new Error('softCapTokens cannot exceed hardCapTokens');
+    throw new ValidationError('softCapTokens cannot exceed hardCapTokens');
   }
   await db
     .delete(systemSettings)
diff --git a/src/lib/services/berth-pdf-parser.ts b/src/lib/services/berth-pdf-parser.ts
index c61f28d..b64a656 100644
--- a/src/lib/services/berth-pdf-parser.ts
+++ b/src/lib/services/berth-pdf-parser.ts
@@ -22,6 +22,8 @@
 
 import { PDFDocument } from 'pdf-lib';
 
+import { ValidationError } from '@/lib/errors';
+
 // ─── shared types ────────────────────────────────────────────────────────────
 
 export type ParserEngine = 'acroform' | 'ocr' | 'ai';
@@ -445,7 +447,7 @@ export async function parseBerthPdf(
   opts: ParseBerthPdfOptions = {},
 ): Promise<ParseResult> {
   if (!isPdfMagic(buffer)) {
-    throw new Error('PDF magic-byte check failed: file does not begin with %PDF-');
+    throw new ValidationError('PDF magic-byte check failed: file does not begin with %PDF-');
   }
   const acro = await tryAcroForm(buffer);
   if (acro && Object.keys(acro.fields).length > 0) return acro;
diff --git a/src/lib/services/brochures.service.ts b/src/lib/services/brochures.service.ts
index e1c5f45..9df5be3 100644
--- a/src/lib/services/brochures.service.ts
+++ b/src/lib/services/brochures.service.ts
@@ -15,7 +15,7 @@ import { and, asc, desc, eq, isNull } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { brochures, brochureVersions, ports } from '@/lib/db/schema';
 import type { Brochure, BrochureVersion } from '@/lib/db/schema';
-import { ForbiddenError, NotFoundError, ValidationError } from '@/lib/errors';
+import { CodedError, ForbiddenError, NotFoundError, ValidationError } from '@/lib/errors';
 import { getStorageBackend } from '@/lib/storage';
 import { buildStoragePath } from '@/lib/minio';
 import { logger } from '@/lib/logger';
@@ -140,7 +140,10 @@ export async function createBrochure(input: CreateBrochureInput): Promise<Brochu
         createdBy: input.createdBy,
       })
       .returning();
-    if (!row) throw new Error('Failed to create brochure');
+    if (!row)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Failed to create brochure',
+      });
     return row;
   });
 }
@@ -177,7 +180,10 @@ export async function updateBrochure(
       .set(updates)
       .where(eq(brochures.id, brochureId))
       .returning();
-    if (!row) throw new Error('Failed to update brochure');
+    if (!row)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Failed to update brochure',
+      });
     return row;
   });
 }
@@ -276,7 +282,10 @@ export async function registerBrochureVersion(
       uploadedBy: input.uploadedBy,
     })
     .returning();
-  if (!row) throw new Error('Failed to record brochure version');
+  if (!row)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to record brochure version',
+    });
   return row;
 }
 
diff --git a/src/lib/services/client-merge.service.ts b/src/lib/services/client-merge.service.ts
index 3c0dd9a..5309d87 100644
--- a/src/lib/services/client-merge.service.ts
+++ b/src/lib/services/client-merge.service.ts
@@ -33,6 +33,7 @@ import {
 import { interests } from '@/lib/db/schema/interests';
 import { berthReservations } from '@/lib/db/schema/reservations';
 import { auditLogs } from '@/lib/db/schema/system';
+import { ConflictError, NotFoundError, ValidationError } from '@/lib/errors';
 
 // ─── Public API ─────────────────────────────────────────────────────────────
 
@@ -81,7 +82,7 @@ export interface MergeResult {
  */
 export async function mergeClients(opts: MergeOptions): Promise<MergeResult> {
   if (opts.winnerId === opts.loserId) {
-    throw new Error('Cannot merge a client into itself');
+    throw new ValidationError('Cannot merge a client into itself');
   }
 
   return await db.transaction(async (tx) => {
@@ -99,16 +100,16 @@ export async function mergeClients(opts: MergeOptions): Promise<MergeResult> {
       .where(eq(clients.id, opts.loserId))
       .for('update');
 
-    if (!winnerRow) throw new Error(`Winner client ${opts.winnerId} not found`);
-    if (!loserRow) throw new Error(`Loser client ${opts.loserId} not found`);
+    if (!winnerRow) throw new NotFoundError('client');
+    if (!loserRow) throw new NotFoundError('client');
     if (winnerRow.portId !== loserRow.portId) {
-      throw new Error('Cannot merge clients across different ports');
+      throw new ValidationError('Cannot merge clients across different ports');
     }
     if (loserRow.mergedIntoClientId) {
-      throw new Error(`Loser ${opts.loserId} already merged into ${loserRow.mergedIntoClientId}`);
+      throw new ConflictError('That client has already been merged into another record.');
     }
     if (winnerRow.archivedAt) {
-      throw new Error('Cannot merge into an archived client');
+      throw new ConflictError('Cannot merge into an archived client');
     }
 
     // ── Snapshot the loser's full state before any mutation. Used by
diff --git a/src/lib/services/crm-invite.service.ts b/src/lib/services/crm-invite.service.ts
index e476f64..b699198 100644
--- a/src/lib/services/crm-invite.service.ts
+++ b/src/lib/services/crm-invite.service.ts
@@ -9,7 +9,7 @@ import { userProfiles } from '@/lib/db/schema/users';
 import { env } from '@/lib/env';
 import { sendEmail } from '@/lib/email';
 import { crmInviteEmail } from '@/lib/email/templates/crm-invite';
-import { ConflictError, NotFoundError, ValidationError } from '@/lib/errors';
+import { CodedError, ConflictError, NotFoundError, ValidationError } from '@/lib/errors';
 import { hashToken, mintToken } from '@/lib/portal/passwords';
 
 const INVITE_TTL_HOURS = 72;
@@ -61,7 +61,10 @@ export async function createCrmInvite(args: {
     })
     .returning({ id: crmUserInvites.id });
 
-  if (!row) throw new Error('Failed to create CRM invite');
+  if (!row)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to create CRM invite',
+    });
 
   const link = `${env.APP_URL}/set-password?token=${raw}`;
   const { subject, html, text } = crmInviteEmail({
diff --git a/src/lib/services/currency.ts b/src/lib/services/currency.ts
index 7f77dca..31a3c0b 100644
--- a/src/lib/services/currency.ts
+++ b/src/lib/services/currency.ts
@@ -1,6 +1,7 @@
 import { db } from '@/lib/db';
 import { currencyRates } from '@/lib/db/schema/system';
 import { eq, and } from 'drizzle-orm';
+import { CodedError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 import { fetchWithTimeout } from '@/lib/fetch-with-timeout';
 
@@ -25,7 +26,10 @@ export async function convert(
 export async function refreshRates(): Promise<void> {
   try {
     const res = await fetchWithTimeout('https://api.frankfurter.dev/v1/latest?base=USD');
-    if (!res.ok) throw new Error(`Frankfurter API error: ${res.status}`);
+    if (!res.ok)
+      throw new CodedError('INTERNAL', {
+        internalMessage: `Frankfurter API error: ${res.status}`,
+      });
     const data = await res.json();
     const rates = data.rates as Record<string, number>;
 
diff --git a/src/lib/services/custom-fields.service.ts b/src/lib/services/custom-fields.service.ts
index 1f3cd45..1cd21b3 100644
--- a/src/lib/services/custom-fields.service.ts
+++ b/src/lib/services/custom-fields.service.ts
@@ -3,7 +3,7 @@ import { and, eq, count } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { customFieldDefinitions, customFieldValues } from '@/lib/db/schema/system';
 import { createAuditLog, type AuditMeta } from '@/lib/audit';
-import { NotFoundError, ValidationError, ConflictError } from '@/lib/errors';
+import { CodedError, NotFoundError, ValidationError, ConflictError } from '@/lib/errors';
 import type { CreateFieldInput, UpdateFieldInput } from '@/lib/validators/custom-fields';
 import type { CustomFieldDefinition } from '@/lib/db/schema/system';
 
@@ -89,7 +89,10 @@ export async function createDefinition(
     .returning();
 
   const created = rows[0];
-  if (!created) throw new Error('Insert failed - no row returned');
+  if (!created)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Custom field definition insert returned no row',
+    });
 
   void createAuditLog({
     userId,
@@ -141,7 +144,10 @@ export async function updateDefinition(
     .returning();
 
   const updated = updateRows[0];
-  if (!updated) throw new Error('Update failed - no row returned');
+  if (!updated)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Custom field definition update returned no row',
+    });
 
   void createAuditLog({
     userId,
diff --git a/src/lib/services/documenso-client.ts b/src/lib/services/documenso-client.ts
index 5e9d145..4b2f6a9 100644
--- a/src/lib/services/documenso-client.ts
+++ b/src/lib/services/documenso-client.ts
@@ -1,7 +1,8 @@
 import { env } from '@/lib/env';
+import { CodedError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 import { getPortDocumensoConfig, type DocumensoApiVersion } from '@/lib/services/port-config';
-import { fetchWithTimeout } from '@/lib/fetch-with-timeout';
+import { fetchWithTimeout, FetchTimeoutError } from '@/lib/fetch-with-timeout';
 
 interface DocumensoCreds {
   baseUrl: string;
@@ -27,19 +28,36 @@ async function documensoFetch(
   portId?: string,
 ): Promise<unknown> {
   const { baseUrl, apiKey } = await resolveCreds(portId);
-  const res = await fetchWithTimeout(`${baseUrl}${path}`, {
-    ...options,
-    headers: {
-      Authorization: `Bearer ${apiKey}`,
-      'Content-Type': 'application/json',
-      ...options?.headers,
-    },
-  });
+  let res: Response;
+  try {
+    res = await fetchWithTimeout(`${baseUrl}${path}`, {
+      ...options,
+      headers: {
+        Authorization: `Bearer ${apiKey}`,
+        'Content-Type': 'application/json',
+        ...options?.headers,
+      },
+    });
+  } catch (err) {
+    if (err instanceof FetchTimeoutError) {
+      throw new CodedError('DOCUMENSO_TIMEOUT', {
+        internalMessage: `${path} timed out after ${err.timeoutMs}ms`,
+      });
+    }
+    throw err;
+  }
 
   if (!res.ok) {
     const err = await res.text();
     logger.error({ path, status: res.status, err, portId }, 'Documenso API error');
-    throw new Error(`Documenso API error: ${res.status}`);
+    if (res.status === 401 || res.status === 403) {
+      throw new CodedError('DOCUMENSO_AUTH_FAILURE', {
+        internalMessage: `${path} → ${res.status}`,
+      });
+    }
+    throw new CodedError('DOCUMENSO_UPSTREAM_ERROR', {
+      internalMessage: `${path} → ${res.status}: ${err}`,
+    });
   }
 
   return res.json();
@@ -242,14 +260,32 @@ export async function sendReminder(
 
 export async function downloadSignedPdf(docId: string, portId?: string): Promise<Buffer> {
   const { baseUrl, apiKey } = await resolveCreds(portId);
-  const res = await fetchWithTimeout(`${baseUrl}/api/v1/documents/${docId}/download`, {
-    headers: { Authorization: `Bearer ${apiKey}` },
-  });
+  const path = `/api/v1/documents/${docId}/download`;
+  let res: Response;
+  try {
+    res = await fetchWithTimeout(`${baseUrl}${path}`, {
+      headers: { Authorization: `Bearer ${apiKey}` },
+    });
+  } catch (err) {
+    if (err instanceof FetchTimeoutError) {
+      throw new CodedError('DOCUMENSO_TIMEOUT', {
+        internalMessage: `${path} timed out after ${err.timeoutMs}ms`,
+      });
+    }
+    throw err;
+  }
 
   if (!res.ok) {
     const err = await res.text();
     logger.error({ docId, status: res.status, err, portId }, 'Documenso download error');
-    throw new Error(`Documenso download error: ${res.status}`);
+    if (res.status === 401 || res.status === 403) {
+      throw new CodedError('DOCUMENSO_AUTH_FAILURE', {
+        internalMessage: `${path} → ${res.status}`,
+      });
+    }
+    throw new CodedError('DOCUMENSO_UPSTREAM_ERROR', {
+      internalMessage: `${path} → ${res.status}: ${err}`,
+    });
   }
 
   const arrayBuffer = await res.arrayBuffer();
@@ -367,7 +403,14 @@ export async function placeFields(
     if (!res.ok) {
       const err = await res.text();
       logger.error({ docId, status: res.status, err, portId }, 'Documenso v2 placeFields error');
-      throw new Error(`Documenso v2 placeFields error: ${res.status}`);
+      if (res.status === 401 || res.status === 403) {
+        throw new CodedError('DOCUMENSO_AUTH_FAILURE', {
+          internalMessage: `v2 placeFields ${docId} → ${res.status}`,
+        });
+      }
+      throw new CodedError('DOCUMENSO_UPSTREAM_ERROR', {
+        internalMessage: `v2 placeFields ${docId} → ${res.status}: ${err}`,
+      });
     }
     return;
   }
@@ -414,7 +457,14 @@ export async function placeFields(
         { docId, status: lastError.status, err: lastError.body, portId },
         'Documenso v1 placeField error',
       );
-      throw new Error(`Documenso v1 placeField error: ${lastError.status}`);
+      if (lastError.status === 401 || lastError.status === 403) {
+        throw new CodedError('DOCUMENSO_AUTH_FAILURE', {
+          internalMessage: `v1 placeField ${docId} → ${lastError.status}`,
+        });
+      }
+      throw new CodedError('DOCUMENSO_UPSTREAM_ERROR', {
+        internalMessage: `v1 placeField ${docId} → ${lastError.status}: ${lastError.body}`,
+      });
     }
   }
 }
@@ -482,6 +532,13 @@ export async function voidDocument(docId: string, portId?: string): Promise<void
   if (!res.ok) {
     const err = await res.text();
     logger.error({ docId, status: res.status, err, portId }, 'Documenso voidDocument error');
-    throw new Error(`Documenso voidDocument error: ${res.status}`);
+    if (res.status === 401 || res.status === 403) {
+      throw new CodedError('DOCUMENSO_AUTH_FAILURE', {
+        internalMessage: `voidDocument ${docId} → ${res.status}`,
+      });
+    }
+    throw new CodedError('DOCUMENSO_UPSTREAM_ERROR', {
+      internalMessage: `voidDocument ${docId} → ${res.status}: ${err}`,
+    });
   }
 }
diff --git a/src/lib/services/documents.service.ts b/src/lib/services/documents.service.ts
index 43ddcf5..6aa6074 100644
--- a/src/lib/services/documents.service.ts
+++ b/src/lib/services/documents.service.ts
@@ -18,7 +18,7 @@ import { userProfiles, userPortRoles } from '@/lib/db/schema/users';
 import { buildListQuery } from '@/lib/db/query-builder';
 import { createAuditLog, type AuditMeta } from '@/lib/audit';
 import { diffEntity } from '@/lib/entity-diff';
-import { NotFoundError, ValidationError, ConflictError } from '@/lib/errors';
+import { CodedError, NotFoundError, ValidationError, ConflictError } from '@/lib/errors';
 import { emitToRoom } from '@/lib/socket/server';
 import { buildStoragePath } from '@/lib/minio';
 import { getStorageBackend } from '@/lib/storage';
@@ -1412,7 +1412,10 @@ export async function createFromWizard(
     })
     .returning();
 
-  if (!doc) throw new Error('Failed to insert document');
+  if (!doc)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to insert document',
+    });
 
   if (data.watchers.length > 0) {
     await assertWatchersInPort(portId, data.watchers);
@@ -1498,7 +1501,10 @@ export async function createFromUpload(
       createdBy: meta.userId,
     })
     .returning();
-  if (!doc) throw new Error('Failed to insert document');
+  if (!doc)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to insert document',
+    });
 
   await db.insert(documentSigners).values(
     data.signers.map((s) => ({
diff --git a/src/lib/services/email-accounts.service.ts b/src/lib/services/email-accounts.service.ts
index 349d880..281980d 100644
--- a/src/lib/services/email-accounts.service.ts
+++ b/src/lib/services/email-accounts.service.ts
@@ -4,7 +4,7 @@ import { db } from '@/lib/db';
 import { emailAccounts } from '@/lib/db/schema/email';
 import { encrypt, decrypt } from '@/lib/utils/encryption';
 import { createAuditLog, type AuditMeta } from '@/lib/audit';
-import { NotFoundError, ForbiddenError } from '@/lib/errors';
+import { CodedError, NotFoundError, ForbiddenError } from '@/lib/errors';
 import type { ConnectAccountInput, ToggleAccountInput } from '@/lib/validators/email';
 
 // ─── Types ────────────────────────────────────────────────────────────────────
@@ -62,7 +62,10 @@ export async function connectAccount(
     .returning();
 
   const account = inserted[0];
-  if (!account) throw new Error('Failed to insert email account');
+  if (!account)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to insert email account',
+    });
 
   void createAuditLog({
     userId: audit.userId,
@@ -104,7 +107,10 @@ export async function toggleAccount(
     .returning();
 
   const updated = updatedRows[0];
-  if (!updated) throw new Error('Failed to update email account');
+  if (!updated)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to update email account',
+    });
 
   return stripCredentials(updated);
 }
diff --git a/src/lib/services/email-compose.service.ts b/src/lib/services/email-compose.service.ts
index a7c4b01..82d62be 100644
--- a/src/lib/services/email-compose.service.ts
+++ b/src/lib/services/email-compose.service.ts
@@ -6,7 +6,7 @@ import { emailAccounts, emailMessages, emailThreads } from '@/lib/db/schema/emai
 import { documents, documentEvents, files } from '@/lib/db/schema/documents';
 import { createAuditLog, type AuditMeta } from '@/lib/audit';
 import { env } from '@/lib/env';
-import { NotFoundError, ForbiddenError } from '@/lib/errors';
+import { CodedError, NotFoundError, ForbiddenError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 import { getDecryptedCredentials } from '@/lib/services/email-accounts.service';
 import { getPortEmailConfig } from '@/lib/services/port-config';
@@ -195,7 +195,10 @@ export async function sendEmail(
       })
       .returning();
     const newThread = newThreadRows[0];
-    if (!newThread) throw new Error('Failed to create email thread');
+    if (!newThread)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Failed to create email thread',
+      });
     threadId = newThread.id;
   }
 
@@ -222,7 +225,10 @@ export async function sendEmail(
     .returning();
 
   const message = messageRows[0];
-  if (!message) throw new Error('Failed to persist outbound email message');
+  if (!message)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to persist outbound email message',
+    });
 
   // Update thread metadata
   await db
diff --git a/src/lib/services/email-threads.service.ts b/src/lib/services/email-threads.service.ts
index cb9bade..34167e8 100644
--- a/src/lib/services/email-threads.service.ts
+++ b/src/lib/services/email-threads.service.ts
@@ -3,7 +3,7 @@ import { and, desc, eq, ilike, or, sql } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { emailAccounts, emailMessages, emailThreads } from '@/lib/db/schema/email';
 import { clientContacts, clients } from '@/lib/db/schema/clients';
-import { NotFoundError } from '@/lib/errors';
+import { CodedError, NotFoundError } from '@/lib/errors';
 import { getDecryptedCredentials } from '@/lib/services/email-accounts.service';
 import { logger } from '@/lib/logger';
 import type { ListThreadsInput } from '@/lib/validators/email';
@@ -160,7 +160,10 @@ export async function ingestMessage(portId: string, parsedEmail: ParsedEmail) {
           })
           .returning();
         const newThread = newThreadRows[0];
-        if (!newThread) throw new Error('Failed to create email thread');
+        if (!newThread)
+          throw new CodedError('INSERT_RETURNING_EMPTY', {
+            internalMessage: 'Failed to create email thread (per-client path)',
+          });
         threadId = newThread.id;
       }
     }
@@ -197,7 +200,10 @@ export async function ingestMessage(portId: string, parsedEmail: ParsedEmail) {
       })
       .returning();
     const newThread = newThreadRows[0];
-    if (!newThread) throw new Error('Failed to create email thread');
+    if (!newThread)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Failed to create email thread (orphan ingest path)',
+      });
     threadId = newThread.id;
   }
 
@@ -219,7 +225,10 @@ export async function ingestMessage(portId: string, parsedEmail: ParsedEmail) {
     .returning();
 
   const message = messageRows[0];
-  if (!message) throw new Error('Failed to insert email message');
+  if (!message)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to insert email message',
+    });
 
   // Update thread's lastMessageAt and messageCount
   await db
diff --git a/src/lib/services/expense-dedup.service.ts b/src/lib/services/expense-dedup.service.ts
index f82d2a4..83b2e96 100644
--- a/src/lib/services/expense-dedup.service.ts
+++ b/src/lib/services/expense-dedup.service.ts
@@ -8,6 +8,7 @@ import { and, between, eq, ne, sql } from 'drizzle-orm';
 
 import { db } from '@/lib/db';
 import { expenses } from '@/lib/db/schema/financial';
+import { NotFoundError, ValidationError } from '@/lib/errors';
 
 const DEDUP_WINDOW_DAYS = 3;
 
@@ -93,7 +94,7 @@ export async function mergeDuplicate(
   portId: string,
 ): Promise<void> {
   if (sourceId === targetId) {
-    throw new Error('Cannot merge an expense into itself');
+    throw new ValidationError('Cannot merge an expense into itself');
   }
 
   await db.transaction(async (tx) => {
@@ -106,7 +107,7 @@ export async function mergeDuplicate(
       .from(expenses)
       .where(and(eq(expenses.id, targetId), eq(expenses.portId, portId)));
     if (!source || !target) {
-      throw new Error('Source or target expense not found in this port');
+      throw new NotFoundError('expense');
     }
 
     const mergedReceipts = Array.from(
diff --git a/src/lib/services/expenses.ts b/src/lib/services/expenses.ts
index b573cc0..c715654 100644
--- a/src/lib/services/expenses.ts
+++ b/src/lib/services/expenses.ts
@@ -160,7 +160,10 @@ export async function createExpense(portId: string, data: CreateExpenseInput, me
     })
     .returning();
 
-  if (!expense) throw new Error('Insert failed');
+  if (!expense)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Expense insert returned no row',
+    });
 
   void createAuditLog({
     userId: meta.userId,
diff --git a/src/lib/services/form-templates.service.ts b/src/lib/services/form-templates.service.ts
index 9ee8ce7..1ba6798 100644
--- a/src/lib/services/form-templates.service.ts
+++ b/src/lib/services/form-templates.service.ts
@@ -3,7 +3,7 @@ import { and, desc, eq } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { formTemplates } from '@/lib/db/schema/documents';
 import { createAuditLog } from '@/lib/audit';
-import { NotFoundError } from '@/lib/errors';
+import { CodedError, NotFoundError } from '@/lib/errors';
 import type {
   CreateFormTemplateInput,
   UpdateFormTemplateInput,
@@ -50,7 +50,10 @@ export async function createFormTemplate(
     })
     .returning();
 
-  if (!tpl) throw new Error('Insert failed');
+  if (!tpl)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Form template insert returned no row',
+    });
 
   void createAuditLog({
     userId: meta.userId,
diff --git a/src/lib/services/gdpr-export.service.ts b/src/lib/services/gdpr-export.service.ts
index 7392cc2..b103374 100644
--- a/src/lib/services/gdpr-export.service.ts
+++ b/src/lib/services/gdpr-export.service.ts
@@ -18,7 +18,7 @@ import { db } from '@/lib/db';
 import { gdprExports, type GdprExport } from '@/lib/db/schema/gdpr';
 import { clients, clientContacts } from '@/lib/db/schema/clients';
 import { ports } from '@/lib/db/schema/ports';
-import { NotFoundError, ValidationError } from '@/lib/errors';
+import { CodedError, NotFoundError, ValidationError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 import { getStorageBackend, presignDownloadUrl } from '@/lib/storage';
 import { getQueue } from '@/lib/queue';
@@ -82,7 +82,10 @@ export async function requestGdprExport(input: RequestExportInput): Promise<Requ
       status: 'pending',
     })
     .returning();
-  if (!row) throw new Error('Failed to create export row');
+  if (!row)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'GDPR export row insert returned no row',
+    });
 
   void createAuditLog({
     userId: input.requestedBy,
@@ -153,9 +156,9 @@ export async function processGdprExportJob(input: ProcessJobInput): Promise<void
     const buffer = await done;
 
     if (buffer.length > MAX_BUNDLE_BYTES) {
-      throw new Error(
-        `GDPR bundle exceeded ${MAX_BUNDLE_BYTES} bytes (got ${buffer.length}); refusing to upload`,
-      );
+      throw new CodedError('INTERNAL', {
+        internalMessage: `GDPR bundle exceeded ${MAX_BUNDLE_BYTES} bytes (got ${buffer.length}); refusing to upload`,
+      });
     }
 
     const port = await db.query.ports.findFirst({ where: eq(ports.id, input.portId) });
diff --git a/src/lib/services/interest-scoring.service.ts b/src/lib/services/interest-scoring.service.ts
index 751bf12..5e07b9d 100644
--- a/src/lib/services/interest-scoring.service.ts
+++ b/src/lib/services/interest-scoring.service.ts
@@ -7,6 +7,7 @@ import { reminders } from '@/lib/db/schema/operations';
 import { emailThreads } from '@/lib/db/schema/email';
 import { logger } from '@/lib/logger';
 import { PIPELINE_STAGES } from '@/lib/constants';
+import { NotFoundError } from '@/lib/errors';
 
 // ─── Types ────────────────────────────────────────────────────────────────────
 
@@ -108,7 +109,7 @@ export async function calculateInterestScore(
   });
 
   if (!interest) {
-    throw new Error(`Interest not found: ${interestId}`);
+    throw new NotFoundError('interest');
   }
 
   // Try cache (port-scoped key)
diff --git a/src/lib/services/invoices.ts b/src/lib/services/invoices.ts
index 02bb48c..63dbbd0 100644
--- a/src/lib/services/invoices.ts
+++ b/src/lib/services/invoices.ts
@@ -12,7 +12,7 @@ import { buildListQuery } from '@/lib/db/query-builder';
 import { createAuditLog, type AuditMeta } from '@/lib/audit';
 import { diffEntity } from '@/lib/entity-diff';
 import { withTransaction } from '@/lib/db/utils';
-import { NotFoundError, ConflictError, ValidationError } from '@/lib/errors';
+import { CodedError, NotFoundError, ConflictError, ValidationError } from '@/lib/errors';
 import { getCountryName } from '@/lib/i18n/countries';
 import { getSubdivisionName } from '@/lib/i18n/subdivisions';
 import { emitToRoom } from '@/lib/socket/server';
@@ -337,7 +337,10 @@ export async function createInvoice(portId: string, data: CreateInvoiceInput, me
       })
       .returning();
 
-    if (!newInvoice) throw new Error('Insert failed');
+    if (!newInvoice)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Invoice insert returned no row',
+      });
 
     // Insert line items
     if (lineItemsData.length > 0) {
@@ -618,7 +621,10 @@ export async function generateInvoicePdf(id: string, portId: string, meta: Audit
     })
     .returning();
 
-  if (!fileRecord) throw new Error('File record insert failed');
+  if (!fileRecord)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Invoice PDF file record insert returned no row',
+    });
 
   await db
     .update(invoices)
diff --git a/src/lib/services/notes.service.ts b/src/lib/services/notes.service.ts
index 643fe68..ea1665c 100644
--- a/src/lib/services/notes.service.ts
+++ b/src/lib/services/notes.service.ts
@@ -6,7 +6,7 @@ import { interestNotes, interests } from '@/lib/db/schema/interests';
 import { yachtNotes, yachts } from '@/lib/db/schema/yachts';
 import { companyNotes, companies } from '@/lib/db/schema/companies';
 import { userProfiles } from '@/lib/db/schema/users';
-import { NotFoundError, ValidationError } from '@/lib/errors';
+import { CodedError, NotFoundError, ValidationError } from '@/lib/errors';
 import type { CreateNoteInput, UpdateNoteInput } from '@/lib/validators/notes';
 
 const EDIT_WINDOW_MS = 15 * 60 * 1000; // 15 minutes
@@ -141,7 +141,10 @@ export async function create(
       .insert(yachtNotes)
       .values({ yachtId: entityId, authorId, content: data.content })
       .returning();
-    if (!note) throw new Error('Insert failed');
+    if (!note)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Yacht note insert returned no row',
+      });
     const profile = await db
       .select({ displayName: userProfiles.displayName })
       .from(userProfiles)
@@ -154,7 +157,10 @@ export async function create(
       .insert(companyNotes)
       .values({ companyId: entityId, authorId, content: data.content })
       .returning();
-    if (!note) throw new Error('Insert failed');
+    if (!note)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Company note insert returned no row',
+      });
     const profile = await db
       .select({ displayName: userProfiles.displayName })
       .from(userProfiles)
@@ -168,7 +174,10 @@ export async function create(
       .values({ clientId: entityId, authorId, content: data.content })
       .returning();
 
-    if (!note) throw new Error('Insert failed');
+    if (!note)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Client note insert returned no row',
+      });
 
     const profile = await db
       .select({ displayName: userProfiles.displayName })
@@ -204,7 +213,10 @@ export async function create(
       .values({ interestId: entityId, authorId, content: data.content })
       .returning();
 
-    if (!note) throw new Error('Insert failed');
+    if (!note)
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Interest note insert returned no row',
+      });
 
     const profile = await db
       .select({ displayName: userProfiles.displayName })
@@ -235,7 +247,9 @@ export async function create(
 
     return { ...note, authorName };
   }
-  throw new Error(`Unsupported entityType: ${entityType as string}`);
+  throw new CodedError('INTERNAL', {
+    internalMessage: `Unsupported entityType: ${entityType as string}`,
+  });
 }
 
 export async function update(
diff --git a/src/lib/services/ocr-providers.ts b/src/lib/services/ocr-providers.ts
index 52bdd25..4b75770 100644
--- a/src/lib/services/ocr-providers.ts
+++ b/src/lib/services/ocr-providers.ts
@@ -6,6 +6,7 @@
 
 import OpenAI from 'openai';
 
+import { CodedError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 import { fetchWithTimeout } from '@/lib/fetch-with-timeout';
 
@@ -140,7 +141,9 @@ async function runClaude({ imageBuffer, mimeType, apiKey, model }: RunArgs): Pro
   });
   if (!res.ok) {
     const detail = await res.text().catch(() => '');
-    throw new Error(`Claude API ${res.status}: ${detail.slice(0, 200)}`);
+    throw new CodedError('OCR_UPSTREAM_ERROR', {
+      internalMessage: `Claude API ${res.status}: ${detail.slice(0, 200)}`,
+    });
   }
   const body = (await res.json()) as {
     id?: string;
diff --git a/src/lib/services/portal-auth.service.ts b/src/lib/services/portal-auth.service.ts
index ce2bd94..780096e 100644
--- a/src/lib/services/portal-auth.service.ts
+++ b/src/lib/services/portal-auth.service.ts
@@ -8,7 +8,13 @@ import { systemSettings } from '@/lib/db/schema/system';
 import { env } from '@/lib/env';
 import { sendEmail } from '@/lib/email';
 import { activationEmail, resetEmail } from '@/lib/email/templates/portal-auth';
-import { ConflictError, NotFoundError, UnauthorizedError, ValidationError } from '@/lib/errors';
+import {
+  CodedError,
+  ConflictError,
+  NotFoundError,
+  UnauthorizedError,
+  ValidationError,
+} from '@/lib/errors';
 import { logger } from '@/lib/logger';
 import { createPortalToken } from '@/lib/portal/auth';
 import { hashPassword, hashToken, mintToken, verifyPassword } from '@/lib/portal/passwords';
@@ -71,7 +77,9 @@ export async function createPortalUser(args: {
     .returning({ id: portalUsers.id });
 
   if (!user) {
-    throw new Error('Failed to create portal user');
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to create portal user',
+    });
   }
 
   await issueActivationToken(user.id, normalizedEmail, args.portId);
diff --git a/src/lib/services/reports.service.ts b/src/lib/services/reports.service.ts
index 7284838..9f019e9 100644
--- a/src/lib/services/reports.service.ts
+++ b/src/lib/services/reports.service.ts
@@ -12,7 +12,7 @@ import { emitToRoom } from '@/lib/socket/server';
 import { getQueue } from '@/lib/queue';
 import { env } from '@/lib/env';
 import { logger } from '@/lib/logger';
-import { NotFoundError } from '@/lib/errors';
+import { CodedError, ConflictError, NotFoundError } from '@/lib/errors';
 
 import {
   fetchPipelineData,
@@ -82,7 +82,9 @@ export async function requestReport(portId: string, userId: string, data: Reques
     .returning();
 
   if (!report) {
-    throw new Error('Failed to create report record');
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to create report record',
+    });
   }
 
   await getQueue('reports').add('generate-report', { reportJobId: report.id });
@@ -149,7 +151,7 @@ export async function getDownloadUrl(reportId: string, portId: string) {
   }
 
   if (report.status !== 'ready' || !report.fileId) {
-    throw new Error('Report is not ready for download');
+    throw new ConflictError('Report is not ready for download');
   }
 
   const file = await db.query.files.findFirst({
@@ -173,7 +175,7 @@ export async function generateReport(reportJobId: string): Promise<void> {
   });
 
   if (!report) {
-    throw new Error(`Report job not found: ${reportJobId}`);
+    throw new NotFoundError('report job');
   }
 
   const { portId, reportType, name, parameters, requestedBy } = report;
@@ -189,7 +191,9 @@ export async function generateReport(reportJobId: string): Promise<void> {
     const typeKey = reportType as ReportType;
     const config = REPORT_TYPE_MAP[typeKey];
     if (!config) {
-      throw new Error(`Unknown report type: ${reportType}`);
+      throw new CodedError('VALIDATION_ERROR', {
+        internalMessage: `Unknown report type: ${reportType}`,
+      });
     }
 
     const params = (parameters ?? {}) as Record<string, unknown>;
@@ -242,7 +246,9 @@ export async function generateReport(reportJobId: string): Promise<void> {
       .returning();
 
     if (!fileRecord) {
-      throw new Error('Failed to insert file record');
+      throw new CodedError('INSERT_RETURNING_EMPTY', {
+        internalMessage: 'Failed to insert file record for generated report',
+      });
     }
 
     // 11. Update generatedReports: status='ready', fileId, completedAt
diff --git a/src/lib/services/residential.service.ts b/src/lib/services/residential.service.ts
index f27ab5e..6e8b6fb 100644
--- a/src/lib/services/residential.service.ts
+++ b/src/lib/services/residential.service.ts
@@ -3,7 +3,7 @@ import { and, eq } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { residentialClients, residentialInterests } from '@/lib/db/schema/residential';
 import { createAuditLog, type AuditMeta } from '@/lib/audit';
-import { NotFoundError } from '@/lib/errors';
+import { CodedError, NotFoundError } from '@/lib/errors';
 import { emitToRoom } from '@/lib/socket/server';
 import { buildListQuery } from '@/lib/db/query-builder';
 import { diffEntity } from '@/lib/entity-diff';
@@ -78,7 +78,10 @@ export async function createResidentialClient(
     .insert(residentialClients)
     .values({ portId, ...data })
     .returning();
-  if (!row) throw new Error('Failed to create residential client');
+  if (!row)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to create residential client',
+    });
 
   void createAuditLog({
     userId: meta.userId,
@@ -249,7 +252,10 @@ export async function createResidentialInterest(
     .insert(residentialInterests)
     .values({ portId, ...data })
     .returning();
-  if (!row) throw new Error('Failed to create residential interest');
+  if (!row)
+    throw new CodedError('INSERT_RETURNING_EMPTY', {
+      internalMessage: 'Failed to create residential interest',
+    });
 
   void createAuditLog({
     userId: meta.userId,
diff --git a/src/lib/services/sales-email-config.service.ts b/src/lib/services/sales-email-config.service.ts
index ebd14a0..755161f 100644
--- a/src/lib/services/sales-email-config.service.ts
+++ b/src/lib/services/sales-email-config.service.ts
@@ -20,6 +20,7 @@
 import nodemailer, { type Transporter } from 'nodemailer';
 
 import { env } from '@/lib/env';
+import { ConflictError } from '@/lib/errors';
 import { decrypt, encrypt } from '@/lib/utils/encryption';
 import { getSetting, upsertSetting } from '@/lib/services/settings.service';
 import type { AuditMeta } from '@/lib/audit';
@@ -323,7 +324,7 @@ export async function createSalesTransporter(portId: string): Promise<{
 }> {
   const cfg = await getSalesEmailConfig(portId);
   if (!cfg.smtpHost) {
-    throw new Error(
+    throw new ConflictError(
       'Sales SMTP not configured for this port. Configure in /admin/email before sending.',
     );
   }
diff --git a/src/lib/services/system-monitoring.service.ts b/src/lib/services/system-monitoring.service.ts
index a581086..f8e1ce7 100644
--- a/src/lib/services/system-monitoring.service.ts
+++ b/src/lib/services/system-monitoring.service.ts
@@ -6,6 +6,7 @@ import { getQueue, QUEUE_CONFIGS, type QueueName } from '@/lib/queue';
 import { createAuditLog } from '@/lib/audit';
 import { env } from '@/lib/env';
 import { sql, desc, eq } from 'drizzle-orm';
+import { NotFoundError } from '@/lib/errors';
 import { logger } from '@/lib/logger';
 
 // ─── Types ────────────────────────────────────────────────────────────────────
@@ -269,7 +270,7 @@ export async function getQueueJobs(
 export async function retryJob(queueName: QueueName, jobId: string, userId: string): Promise<void> {
   const queue = getQueue(queueName);
   const job = await queue.getJob(jobId);
-  if (!job) throw new Error(`Job ${jobId} not found in queue ${queueName}`);
+  if (!job) throw new NotFoundError('queue job');
 
   await job.retry();
 
@@ -294,7 +295,7 @@ export async function deleteJob(
 ): Promise<void> {
   const queue = getQueue(queueName);
   const job = await queue.getJob(jobId);
-  if (!job) throw new Error(`Job ${jobId} not found in queue ${queueName}`);
+  if (!job) throw new NotFoundError('queue job');
 
   await job.remove();
 
diff --git a/src/lib/services/umami.service.ts b/src/lib/services/umami.service.ts
index af91377..5261992 100644
--- a/src/lib/services/umami.service.ts
+++ b/src/lib/services/umami.service.ts
@@ -21,6 +21,7 @@ import { and, eq, inArray } from 'drizzle-orm';
 import { db } from '@/lib/db';
 import { systemSettings } from '@/lib/db/schema/system';
 import { rangeToBounds, type DateRange } from '@/lib/analytics/range';
+import { CodedError } from '@/lib/errors';
 import { fetchWithTimeout } from '@/lib/fetch-with-timeout';
 
 // ─── Settings access ────────────────────────────────────────────────────────
@@ -87,10 +88,15 @@ async function loginAndCache(apiUrl: string, username: string, password: string)
     body: JSON.stringify({ username, password }),
   });
   if (!res.ok) {
-    throw new Error(`Umami login failed: ${res.status} ${res.statusText}`);
+    throw new CodedError('UMAMI_UPSTREAM_ERROR', {
+      internalMessage: `Umami login failed: ${res.status} ${res.statusText}`,
+    });
   }
   const body = (await res.json()) as { token?: string };
-  if (!body.token) throw new Error('Umami login response missing token');
+  if (!body.token)
+    throw new CodedError('UMAMI_UPSTREAM_ERROR', {
+      internalMessage: 'Umami login response missing token',
+    });
   jwtCache.set(`${apiUrl}::${username}`, {
     token: body.token,
     expiresAt: Date.now() + JWT_TTL_MS,
@@ -101,7 +107,9 @@ async function loginAndCache(apiUrl: string, username: string, password: string)
 async function resolveBearer(config: UmamiPortConfig): Promise<string> {
   if (config.apiToken) return config.apiToken;
   if (!config.username || !config.password) {
-    throw new Error('Umami is misconfigured: no API token and no username/password.');
+    throw new CodedError('UMAMI_NOT_CONFIGURED', {
+      internalMessage: 'Umami is misconfigured: no API token and no username/password.',
+    });
   }
   const cacheKey = `${config.apiUrl}::${config.username}`;
   const cached = jwtCache.get(cacheKey);
@@ -136,13 +144,17 @@ async function umamiFetch<T>(
   if (res.status === 401 || res.status === 403) {
     // Bearer rejected - drop cached JWT so next call re-logs in.
     if (config.username) jwtCache.delete(`${config.apiUrl}::${config.username}`);
-    throw new Error(`Umami unauthorized: ${res.status}`);
+    throw new CodedError('UMAMI_UPSTREAM_ERROR', {
+      internalMessage: `Umami unauthorized: ${res.status}`,
+    });
   }
   if (!res.ok) {
     const text = await res.text().catch(() => '');
-    throw new Error(
-      `Umami ${path} failed: ${res.status} ${res.statusText}${text ? ` - ${text}` : ''}`,
-    );
+    throw new CodedError('UMAMI_UPSTREAM_ERROR', {
+      internalMessage: `Umami ${path} failed: ${res.status} ${res.statusText}${
+        text ? ` - ${text}` : ''
+      }`,
+    });
   }
   return (await res.json()) as T;
 }
@@ -248,7 +260,9 @@ export async function getActiveVisitors(portId: string): Promise<UmamiActiveVisi
 export async function testConnection(portId: string): Promise<{ ok: true; visitors: number }> {
   const config = await loadUmamiConfig(portId);
   if (!config) {
-    throw new Error('Umami is not configured for this port.');
+    throw new CodedError('UMAMI_NOT_CONFIGURED', {
+      internalMessage: 'Umami is not configured for this port.',
+    });
   }
   const result = await umamiFetch<UmamiActiveVisitors>(
     config,
diff --git a/tests/integration/dedup/client-merge.test.ts b/tests/integration/dedup/client-merge.test.ts
index ecad124..160270e 100644
--- a/tests/integration/dedup/client-merge.test.ts
+++ b/tests/integration/dedup/client-merge.test.ts
@@ -130,7 +130,7 @@ describe('mergeClients', () => {
     const winner2 = await makeClient({ portId: port.id });
     await expect(
       mergeClients({ winnerId: winner2.id, loserId: loser.id, mergedBy: 'u' }),
-    ).rejects.toThrow(/already merged/i);
+    ).rejects.toThrow(/already been merged/i);
   });
 
   it('drops duplicate contact rows during reattach', async () => {
diff --git a/tests/integration/expense-dedup.test.ts b/tests/integration/expense-dedup.test.ts
index da8f060..8afffda 100644
--- a/tests/integration/expense-dedup.test.ts
+++ b/tests/integration/expense-dedup.test.ts
@@ -197,6 +197,8 @@ describe('expense dedup', () => {
       expenseDate: new Date('2026-04-15T12:00:00Z'),
     });
     await expect(mergeDuplicate(a.id, a.id, portA.id)).rejects.toThrow(/itself/);
-    await expect(mergeDuplicate(a.id, b.id, portA.id)).rejects.toThrow(/not found/);
+    await expect(mergeDuplicate(a.id, b.id, portA.id)).rejects.toThrow(
+      /couldn't find that expense/,
+    );
   });
 });
diff --git a/tests/unit/interest-scoring.test.ts b/tests/unit/interest-scoring.test.ts
index 1fe891c..bcda28d 100644
--- a/tests/unit/interest-scoring.test.ts
+++ b/tests/unit/interest-scoring.test.ts
@@ -306,7 +306,9 @@ describe('calculateInterestScore', () => {
 
   it('throws when interest not found', async () => {
     (db.query.interests.findFirst as ReturnType<typeof vi.fn>).mockResolvedValue(null);
-    await expect(calculateInterestScore('missing', 'p1')).rejects.toThrow('Interest not found');
+    await expect(calculateInterestScore('missing', 'p1')).rejects.toThrow(
+      /couldn't find that interest/,
+    );
   });
 
   it('returns cached result when redis has a hit (after port-scope DB check)', async () => {
diff --git a/tests/unit/services/documenso-place-fields.test.ts b/tests/unit/services/documenso-place-fields.test.ts
index ee725e2..e848ec5 100644
--- a/tests/unit/services/documenso-place-fields.test.ts
+++ b/tests/unit/services/documenso-place-fields.test.ts
@@ -147,7 +147,7 @@ describe('placeFields v2 dispatch', () => {
         ],
         'port-1',
       ),
-    ).rejects.toThrow(/v2 placeFields/);
+    ).rejects.toThrow(/signing service didn't respond/);
   });
 });
 
@@ -235,7 +235,7 @@ describe('placeFields v1 dispatch', () => {
         ],
         'port-1',
       ),
-    ).rejects.toThrow(/v1 placeField/);
+    ).rejects.toThrow(/signing service didn't respond/);
   });
 });
 
@@ -322,6 +322,6 @@ describe('voidDocument', () => {
   it('throws on other non-2xx responses', async () => {
     configurePort('v2');
     fetchMock.mockResolvedValueOnce(new Response('boom', { status: 500 }));
-    await expect(voidDocument('env-1', 'port-1')).rejects.toThrow(/voidDocument/);
+    await expect(voidDocument('env-1', 'port-1')).rejects.toThrow(/signing service didn't respond/);
   });
 });