diff --git a/app/core/hooks.py b/app/core/hooks.py
index 97cd1cd..8acfd59 100644
--- a/app/core/hooks.py
+++ b/app/core/hooks.py
@@ -50,8 +50,8 @@ class HookRegistry:
     def __new__(cls) -> HookRegistry:
         if cls._instance is None:
             cls._instance = super().__new__(cls)
-            cls._instance._actions: dict[str, list[tuple[int, Callable]]] = defaultdict(list)
-            cls._instance._filters: dict[str, list[tuple[int, Callable]]] = defaultdict(list)
+            cls._instance._actions: dict[str, list[tuple[int, Callable, str]]] = defaultdict(list)
+            cls._instance._filters: dict[str, list[tuple[int, Callable, str]]] = defaultdict(list)
         return cls._instance
 
     # ─── Registration ───
diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index cf3ce82..013f484 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React from 'react';
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
 import { AppRouter } from '@/routes';
@@ -21,10 +22,10 @@ function QueryClientWrapper({ children }: { children: React.ReactNode }) {
       },
       mutations: {
         retry: 0,
-        onError: (error: any) => {
+        onError: (error: unknown) => { const errObj = asError(error);
           // Don't show toast for 401 (handled by auth)
-          if (error?.status === 401) return;
-          const msg = error?.detail || error?.message || 'Ein Fehler ist aufgetreten';
+          if (errObj?.status === 401) return;
+          const msg = errObj?.detail || errObj?.message || 'Ein Fehler ist aufgetreten';
           toast.error(msg);
         },
       },
diff --git a/frontend/src/api/auth.ts b/frontend/src/api/auth.ts
index e247da4..18005d9 100644
--- a/frontend/src/api/auth.ts
+++ b/frontend/src/api/auth.ts
@@ -2,6 +2,7 @@
  * Authentication hooks: login, logout, current user, password reset, tenant switching.
  */
 
+import { asError } from '@/utils/errorTypes';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { apiPost, apiGet, setCsrfToken } from './client';
 import { useAuthStore } from '@/store/authStore';
@@ -44,8 +45,8 @@ export function useLogin() {
         setCsrfToken(data.csrf_token);
       }
     },
-    onError: (error: any) => {
-      setError(error.message || 'Login failed');
+    onError: (error: unknown) => { const errObj = asError(error);
+      setError(errObj.message || 'Login failed');
     },
   });
 }
diff --git a/frontend/src/components/AddressList.tsx b/frontend/src/components/AddressList.tsx
index bc778ad..be1828f 100644
--- a/frontend/src/components/AddressList.tsx
+++ b/frontend/src/components/AddressList.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import { apiGet, apiPost, apiPatch, apiDelete } from '@/api/client';
@@ -49,8 +50,8 @@ export function AddressList({ entityType, entityId }: AddressListProps) {
         `/addresses?entity_type=${entityType}&entity_id=${entityId}`
       );
       setAddresses(data.items);
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     } finally {
       setLoading(false);
     }
@@ -65,8 +66,8 @@ export function AddressList({ entityType, entityId }: AddressListProps) {
     try {
       await apiDelete(`/addresses/${id}`);
       await fetchAddresses();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
@@ -74,8 +75,8 @@ export function AddressList({ entityType, entityId }: AddressListProps) {
     try {
       await apiPatch(`/addresses/${id}`, { is_default: true });
       await fetchAddresses();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
@@ -89,8 +90,8 @@ export function AddressList({ entityType, entityId }: AddressListProps) {
       setShowForm(false);
       setEditingAddress(null);
       await fetchAddresses();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/components/SavedFilters.tsx b/frontend/src/components/SavedFilters.tsx
index ae226de..a0f7c9a 100644
--- a/frontend/src/components/SavedFilters.tsx
+++ b/frontend/src/components/SavedFilters.tsx
@@ -3,6 +3,7 @@
  * Integrates into list views (Contacts, Mail, Calendar, DMS).
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Button } from '@/components/ui/Button';
@@ -44,8 +45,8 @@ export function SavedFilters({ entityType, currentCriteria, onLoadFilter }: Save
       toast.success(t('savedFilters.saved'));
       setFilterName('');
       setSaveModalOpen(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -53,8 +54,8 @@ export function SavedFilters({ entityType, currentCriteria, onLoadFilter }: Save
     try {
       await deleteMutation.mutateAsync(id);
       toast.success(t('savedFilters.deleted'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/components/agents/AgentChat.tsx b/frontend/src/components/agents/AgentChat.tsx
index f6bf270..e87a238 100644
--- a/frontend/src/components/agents/AgentChat.tsx
+++ b/frontend/src/components/agents/AgentChat.tsx
@@ -1,6 +1,6 @@
 import { useState, useRef, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
-import { PaperAirplaneIcon, StopCircleIcon, CurrencyDollarIcon } from '@heroicons/react/24/outline';
+import { Send, CircleStop, DollarSign } from 'lucide-react';
 
 interface AgentStep {
   step_number: number;
@@ -40,27 +40,27 @@ export function AgentChat({ agentId, agentName }: AgentChatProps) {
     const eventSource = new EventSource(url);
     eventSourceRef.current = eventSource;
 
-    eventSource.addEventListener('step', (e) => {
+    eventSource.addEventListener('step', (e: MessageEvent) => {
       const step = JSON.parse(e.data) as AgentStep;
       setSteps((prev) => [...prev, step]);
       setTotalCost((prev) => prev + (step.cost_usd || 0));
     });
 
-    eventSource.addEventListener('status', (e) => {
+    eventSource.addEventListener('status', (e: MessageEvent) => {
       const data = JSON.parse(e.data);
       if (data.status === 'running') {
         setMessages((prev) => [...prev, `Step ${data.step}: ${data.action || 'Thinking...'}`]);
       }
     });
 
-    eventSource.addEventListener('done', (e) => {
+    eventSource.addEventListener('done', (e: MessageEvent) => {
       const data = JSON.parse(e.data);
       setMessages((prev) => [...prev, `Agent: ${data.final_content}`]);
       setIsRunning(false);
       eventSource.close();
     });
 
-    eventSource.addEventListener('error', (e) => {
+    eventSource.addEventListener('error', (e: MessageEvent) => {
       try {
         const data = JSON.parse(e.data);
         setMessages((prev) => [...prev, `Error: ${data.error}`]);
@@ -93,7 +93,7 @@ export function AgentChat({ agentId, agentName }: AgentChatProps) {
           </label>
           {totalCost > 0 && (
             <span className="flex items-center gap-1 text-sm text-gray-600 dark:text-gray-400">
-              <CurrencyDollarIcon className="w-4 h-4" />
+              <DollarSign className="w-4 h-4" />
               {totalCost.toFixed(6)}
             </span>
           )}
@@ -133,11 +133,11 @@ export function AgentChat({ agentId, agentName }: AgentChatProps) {
           />
           {isRunning ? (
             <button onClick={handleStop} className="p-2 rounded-lg bg-red-500 text-white hover:bg-red-600 min-h-[44px] min-w-[44px]" aria-label={t('agents.stop')}>
-              <StopCircleIcon className="w-5 h-5" />
+              <CircleStop className="w-5 h-5" />
             </button>
           ) : (
             <button onClick={handleSend} disabled={!input.trim()} className="p-2 rounded-lg bg-primary-600 text-white hover:bg-primary-700 disabled:opacity-50 min-h-[44px] min-w-[44px]" aria-label={t('agents.send')}>
-              <PaperAirplaneIcon className="w-5 h-5" />
+              <Send className="w-5 h-5" />
             </button>
           )}
         </div>
diff --git a/frontend/src/components/agents/AgentEditor.tsx b/frontend/src/components/agents/AgentEditor.tsx
index 55950cb..93ff512 100644
--- a/frontend/src/components/agents/AgentEditor.tsx
+++ b/frontend/src/components/agents/AgentEditor.tsx
@@ -70,7 +70,7 @@ const commonModels = [
 
 export function AgentEditor({ agent, onSaved, onCancel }: AgentEditorProps) {
   const { t } = useTranslation();
-  const { toast } = useToast();
+  const toast = useToast();
   const { data: tools = [] } = useAgentToolsFull();
   const { data: skills = [] } = useAgentSkills();
   const createAgent = useCreateAgent();
@@ -83,17 +83,17 @@ export function AgentEditor({ agent, onSaved, onCancel }: AgentEditorProps) {
         name: agent.name,
         description: agent.description || '',
         system_prompt: agent.system_prompt || '',
-        llm_model: agent.llm_model,
+        llm_model: agent.llm_model || agent.model || '',
         tool_ids: agent.tool_ids || [],
         skill_ids: agent.skill_ids || [],
-        max_steps: agent.max_steps,
-        max_duration_seconds: agent.max_duration_seconds,
-        budget_limit_usd: agent.budget_limit_usd,
-        temperature: agent.temperature,
-        max_tokens: agent.max_tokens,
-        trace_mode: agent.trace_mode,
+        max_steps: agent.max_steps ?? 20,
+        max_duration_seconds: agent.max_duration_seconds ?? 300,
+        budget_limit_usd: agent.budget_limit_usd ?? agent.budget_limit ?? 1.0,
+        temperature: agent.temperature ?? 0.3,
+        max_tokens: agent.max_tokens ?? 1000,
+        trace_mode: (agent.trace_mode === 'extended' ? 'extended' : 'standard') as 'standard' | 'extended',
         mode: agent.mode,
-        is_active: agent.is_active,
+        is_active: agent.is_active ?? agent.active ?? true,
         trigger_config: agent.trigger_config || {},
         ai_use_case_metadata: agent.ai_use_case_metadata || {},
       };
@@ -142,28 +142,28 @@ export function AgentEditor({ agent, onSaved, onCancel }: AgentEditorProps) {
     try {
       if (agent) {
         const updated = await updateAgent.mutateAsync({ id: agent.id, data });
-        toast({ title: t('agent.saved'), variant: 'success' });
+        toast.success(t('agent.saved'));
         onSaved?.(updated);
       } else {
         const created = await createAgent.mutateAsync(data);
-        toast({ title: t('agent.created'), variant: 'success' });
+        toast.success(t('agent.created'));
         onSaved?.(created);
       }
     } catch {
-      toast({ title: t('agent.saveFailed'), variant: 'error' });
+      toast.error(t('agent.saveFailed'));
     }
   };
 
   const handleTestRun = async () => {
     if (!agent) {
-      toast({ title: t('agent.saveBeforeTest'), variant: 'warning' });
+      toast.warning(t('agent.saveBeforeTest'));
       return;
     }
     try {
       await testRunAgent.mutateAsync(agent.id);
-      toast({ title: t('agent.testRunOk'), variant: 'success' });
+      toast.success(t('agent.testRunOk'));
     } catch {
-      toast({ title: t('agent.testRunFailed'), variant: 'error' });
+      toast.error(t('agent.testRunFailed'));
     }
   };
 
@@ -268,11 +268,11 @@ export function AgentEditor({ agent, onSaved, onCancel }: AgentEditorProps) {
         ) : (
           <div className="grid grid-cols-1 md:grid-cols-2 gap-2 max-h-40 overflow-y-auto" role="group" aria-label={t('agent.tools')}>
             {tools.map((tool) => (
-              <label key={tool.id} className="flex items-center gap-2 p-2 rounded-md hover:bg-secondary-50 cursor-pointer text-sm min-h-touch">
+              <label key={tool.id || tool.name} className="flex items-center gap-2 p-2 rounded-md hover:bg-secondary-50 cursor-pointer text-sm min-h-touch">
                 <input
                   type="checkbox"
-                  checked={selectedToolIds.includes(tool.id)}
-                  onChange={() => toggleArrayValue('tool_ids', tool.id)}
+                  checked={selectedToolIds.includes(tool.id || tool.name)}
+                  onChange={() => toggleArrayValue('tool_ids', tool.id || tool.name)}
                   className="rounded border-secondary-300 text-primary-600 focus:ring-primary-500"
                 />
                 <div>
diff --git a/frontend/src/components/agents/AgentMonitor.tsx b/frontend/src/components/agents/AgentMonitor.tsx
index 7ccf97d..7539934 100644
--- a/frontend/src/components/agents/AgentMonitor.tsx
+++ b/frontend/src/components/agents/AgentMonitor.tsx
@@ -1,6 +1,6 @@
 import { useTranslation } from 'react-i18next';
 import { useQuery } from '@tanstack/react-query';
-import { ChartBarIcon, ExclamationTriangleIcon, CurrencyDollarIcon, ClockIcon } from '@heroicons/react/24/outline';
+import { BarChart3, AlertTriangle, DollarSign, Clock } from 'lucide-react';
 
 export function AgentMonitor() {
   const { t } = useTranslation();
@@ -32,28 +32,28 @@ export function AgentMonitor() {
       <div className="grid grid-cols-1 md:grid-cols-4 gap-4">
         <div className="p-4 rounded-lg bg-primary-50 dark:bg-primary-900/20">
           <div className="flex items-center gap-2 mb-2">
-            <ClockIcon className="w-5 h-5 text-primary-600" />
+            <Clock className="w-5 h-5 text-primary-600" />
             <span className="text-sm text-gray-600 dark:text-gray-400">{t('agents.activeRuns')}</span>
           </div>
           <p className="text-2xl font-bold text-gray-900 dark:text-white">{stats?.active_runs ?? 0}</p>
         </div>
         <div className="p-4 rounded-lg bg-green-50 dark:bg-green-900/20">
           <div className="flex items-center gap-2 mb-2">
-            <CurrencyDollarIcon className="w-5 h-5 text-green-600" />
+            <DollarSign className="w-5 h-5 text-green-600" />
             <span className="text-sm text-gray-600 dark:text-gray-400">{t('agents.totalBudget')}</span>
           </div>
           <p className="text-2xl font-bold text-gray-900 dark:text-white">${(stats?.total_budget_usd ?? 0).toFixed(4)}</p>
         </div>
         <div className="p-4 rounded-lg bg-blue-50 dark:bg-blue-900/20">
           <div className="flex items-center gap-2 mb-2">
-            <ChartBarIcon className="w-5 h-5 text-blue-600" />
+            <BarChart3 className="w-5 h-5 text-blue-600" />
             <span className="text-sm text-gray-600 dark:text-gray-400">{t('agents.runsPerHour')}</span>
           </div>
           <p className="text-2xl font-bold text-gray-900 dark:text-white">{stats?.runs_per_hour ?? 0}</p>
         </div>
         <div className="p-4 rounded-lg bg-red-50 dark:bg-red-900/20">
           <div className="flex items-center gap-2 mb-2">
-            <ExclamationTriangleIcon className="w-5 h-5 text-red-600" />
+            <AlertTriangle className="w-5 h-5 text-red-600" />
             <span className="text-sm text-gray-600 dark:text-gray-400">{t('agents.errorRate')}</span>
           </div>
           <p className="text-2xl font-bold text-gray-900 dark:text-white">{(stats?.error_rate ?? 0).toFixed(1)}%</p>
diff --git a/frontend/src/components/agents/AgentRunLog.tsx b/frontend/src/components/agents/AgentRunLog.tsx
index c83c694..b77dca3 100644
--- a/frontend/src/components/agents/AgentRunLog.tsx
+++ b/frontend/src/components/agents/AgentRunLog.tsx
@@ -1,7 +1,7 @@
 import { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useQuery } from '@tanstack/react-query';
-import { ArrowDownTrayIcon } from '@heroicons/react/24/outline';
+import { Download } from 'lucide-react';
 
 interface RunStep {
   id: string;
@@ -52,10 +52,10 @@ export function AgentRunLog({ agentId, runId }: AgentRunLogProps) {
         <h2 className="text-lg font-semibold text-gray-900 dark:text-white">{t('agents.runLog')}</h2>
         <div className="flex items-center gap-2">
           <button onClick={() => handleExport('json')} className="p-2 rounded-lg text-gray-600 hover:bg-gray-100 dark:hover:bg-gray-800 min-h-[44px] min-w-[44px]" aria-label={t('agents.exportJson')}>
-            <ArrowDownTrayIcon className="w-5 h-5" />
+            <Download className="w-5 h-5" />
           </button>
           <button onClick={() => handleExport('csv')} className="p-2 rounded-lg text-gray-600 hover:bg-gray-100 dark:hover:bg-gray-800 min-h-[44px] min-w-[44px]" aria-label={t('agents.exportCsv')}>
-            <ArrowDownTrayIcon className="w-5 h-5" />
+            <Download className="w-5 h-5" />
           </button>
         </div>
       </div>
diff --git a/frontend/src/components/common/ABACRuleEditor.tsx b/frontend/src/components/common/ABACRuleEditor.tsx
index 37bf30c..b5078f4 100644
--- a/frontend/src/components/common/ABACRuleEditor.tsx
+++ b/frontend/src/components/common/ABACRuleEditor.tsx
@@ -9,6 +9,7 @@
  * - Text-basierte Vorschau der Policy
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useCallback, useMemo } from 'react';
 import clsx from 'clsx';
 import {
@@ -439,8 +440,8 @@ function PolicyForm({ initial, entityType, onSave, onCancel }: PolicyFormProps)
         await createPolicy.mutateAsync(payload);
       }
       onSave();
-    } catch (err: any) {
-      setError(err?.message || t('abac.saveError', 'Failed to save policy'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj?.message || t('abac.saveError', 'Failed to save policy'));
     }
   }, [
     initial,
diff --git a/frontend/src/components/common/SaveFilterDialog.tsx b/frontend/src/components/common/SaveFilterDialog.tsx
index 832792c..0d0f762 100644
--- a/frontend/src/components/common/SaveFilterDialog.tsx
+++ b/frontend/src/components/common/SaveFilterDialog.tsx
@@ -7,6 +7,7 @@
  * shows a success toast, and closes.
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Modal } from '@/components/ui/Modal';
@@ -98,9 +99,9 @@ export function SaveFilterDialog({
       );
       setName('');
       onClose();
-    } catch (err: any) {
+    } catch (err: unknown) { const errObj = asError(err);
       toast.error(
-        err?.message || t('savedFilters.saveError', 'Filter konnte nicht gespeichert werden')
+        errObj?.message || t('savedFilters.saveError', 'Filter konnte nicht gespeichert werden')
       );
     } finally {
       setSubmitting(false);
diff --git a/frontend/src/components/common/SavedFilterBar.tsx b/frontend/src/components/common/SavedFilterBar.tsx
index 76dc3d9..7458aa6 100644
--- a/frontend/src/components/common/SavedFilterBar.tsx
+++ b/frontend/src/components/common/SavedFilterBar.tsx
@@ -10,6 +10,7 @@
  *   • Click-outside-to-close dropdown behaviour
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useRef, useEffect, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Button } from '@/components/ui/Button';
@@ -86,8 +87,8 @@ export function SavedFilterBar({
   const handleDelete = useCallback(
     async (e: React.MouseEvent, id: string) => {
       e.stopPropagation();      try {        await deleteMutation.mutateAsync(id);        if (activeFilterId === id) setActiveFilterId(null);        toast.success(t('savedFilters.deleted', 'Filter gelöscht'));
-      } catch (err: any) {
-        toast.error(err?.message || t('common.error', 'Fehler'));
+      } catch (err: unknown) { const errObj = asError(err);
+        toast.error(errObj?.message || t('common.error', 'Fehler'));
       }    },    [deleteMutation, activeFilterId, toast, t]
   );
 
diff --git a/frontend/src/components/contacts/ContactDetail.tsx b/frontend/src/components/contacts/ContactDetail.tsx
index 96cd63b..20db1c7 100644
--- a/frontend/src/components/contacts/ContactDetail.tsx
+++ b/frontend/src/components/contacts/ContactDetail.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Button } from '@/components/ui/Button';
@@ -245,8 +246,8 @@ export function ContactDetail({ contact, loading, onEdit, onDeleted, dataTestId
       await deleteMutation.mutateAsync({ id: contact.id });
       toast.success(t('contacts.deleted'));
       onDeleted();
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -261,8 +262,8 @@ export function ContactDetail({ contact, loading, onEdit, onDeleted, dataTestId
       }
       setPersonModalOpen(false);
       setEditingPerson(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -271,8 +272,8 @@ export function ContactDetail({ contact, loading, onEdit, onDeleted, dataTestId
     try {
       await deletePersonMutation.mutateAsync({ contactId: contact.id, personId: person.id });
       toast.success(t('contacts.personDeleted'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/components/contacts/ContactEditForm.tsx b/frontend/src/components/contacts/ContactEditForm.tsx
index 4847a35..b799b02 100644
--- a/frontend/src/components/contacts/ContactEditForm.tsx
+++ b/frontend/src/components/contacts/ContactEditForm.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useEffect, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -205,13 +206,13 @@ export function ContactEditForm({ onClose, contact, onSaved }: ContactEditFormPr
       if (savedId && customFieldDefs.length > 0 && Object.keys(customValues).length > 0) {
         try {
           await updateCustomFields.mutateAsync({ contactId: savedId, values: customValues });
-        } catch (cfErr: any) {
-          console.error('Custom fields save failed:', cfErr);
+        } catch (cfErr: unknown) { const errObj = asError(cfErr);
+          console.error('Custom fields save failed:', errObj);
         }
       }
       onClose();
-    } catch (err: any) {
-      toast.error(err.message || (isEdit ? t('contacts.updateFailed') : t('contacts.createFailed')));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || (isEdit ? t('contacts.updateFailed') : t('contacts.createFailed')));
     }
   };
 
diff --git a/frontend/src/components/contacts/ContactEditModal.tsx b/frontend/src/components/contacts/ContactEditModal.tsx
index ba9bd84..0389fe9 100644
--- a/frontend/src/components/contacts/ContactEditModal.tsx
+++ b/frontend/src/components/contacts/ContactEditModal.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useEffect, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -209,14 +210,14 @@ export function ContactEditModal({ open, onClose, contact, onSaved }: ContactEdi
       if (savedId && customFieldDefs.length > 0 && Object.keys(customValues).length > 0) {
         try {
           await updateCustomFields.mutateAsync({ contactId: savedId, values: customValues });
-        } catch (cfErr: any) {
+        } catch (cfErr: unknown) { const errObj = asError(cfErr);
           // Don't fail the whole save if custom fields fail
-          console.error('Custom fields save failed:', cfErr);
+          console.error('Custom fields save failed:', errObj);
         }
       }
       onClose();
-    } catch (err: any) {
-      toast.error(err.message || (isEdit ? t('contacts.updateFailed') : t('contacts.createFailed')));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || (isEdit ? t('contacts.updateFailed') : t('contacts.createFailed')));
     }
   };
 
diff --git a/frontend/src/components/contacts/ContactFolderTree.tsx b/frontend/src/components/contacts/ContactFolderTree.tsx
index b85dbbb..759c0cf 100644
--- a/frontend/src/components/contacts/ContactFolderTree.tsx
+++ b/frontend/src/components/contacts/ContactFolderTree.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect, useRef, useCallback } from 'react';
 import { createPortal } from 'react-dom';
 import clsx from 'clsx';
@@ -306,8 +307,8 @@ export function ContactFolderTree({
     const name = prompt('Ordnername:');
     if (!name) return;
     createFolderMut.mutate({ name }, {
-      onError: (err: any) => {
-        const msg = err?.response?.data?.detail?.detail || err?.response?.data?.detail || err?.message || 'Fehler beim Anlegen';
+      onError: (err: unknown) => { const errObj = asError(err);
+        const msg = errObj?.response?.data?.detail?.detail || errObj?.response?.data?.detail || errObj?.message || 'Fehler beim Anlegen';
         toast.error(typeof msg === 'string' ? msg : 'Fehler beim Anlegen des Ordners');
       },
     });
@@ -318,8 +319,8 @@ export function ContactFolderTree({
     const newName = prompt('Neuer Name:', folder?.name || '');
     if (!newName) return;
     updateFolderMut.mutate({ id, data: { name: newName } }, {
-      onError: (err: any) => {
-        const msg = err?.response?.data?.detail?.detail || err?.response?.data?.detail || err?.message || 'Fehler beim Umbenennen';
+      onError: (err: unknown) => { const errObj = asError(err);
+        const msg = errObj?.response?.data?.detail?.detail || errObj?.response?.data?.detail || errObj?.message || 'Fehler beim Umbenennen';
         toast.error(typeof msg === 'string' ? msg : 'Fehler beim Umbenennen');
       },
     });
@@ -328,8 +329,8 @@ export function ContactFolderTree({
   const handleDelete = (id: string) => {
     if (!confirm('Ordner l\u00f6schen? Kontakte bleiben erhalten, werden aber keinem Ordner mehr zugeordnet.')) return;
     deleteFolderMut.mutate(id, {
-      onError: (err: any) => {
-        const msg = err?.response?.data?.detail?.detail || err?.response?.data?.detail || err?.message || 'Fehler beim L\u00f6schen';
+      onError: (err: unknown) => { const errObj = asError(err);
+        const msg = errObj?.response?.data?.detail?.detail || errObj?.response?.data?.detail || errObj?.message || 'Fehler beim L\u00f6schen';
         toast.error(typeof msg === 'string' ? msg : 'Fehler beim L\u00f6schen');
       },
     });
diff --git a/frontend/src/components/import-export/ExportPanel.tsx b/frontend/src/components/import-export/ExportPanel.tsx
index c1ecb03..5fbffee 100644
--- a/frontend/src/components/import-export/ExportPanel.tsx
+++ b/frontend/src/components/import-export/ExportPanel.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Download, Loader2, FileText, CheckCircle } from 'lucide-react';
@@ -41,9 +42,9 @@ export function ExportPanel() {
       toast.success(
         t('importExport.exportSuccess', 'Export erfolgreich heruntergeladen')
       );
-    } catch (err: any) {
+    } catch (err: unknown) { const errObj = asError(err);
       toast.error(
-        err?.message || t('importExport.exportFailed', 'Export fehlgeschlagen')
+        errObj?.message || t('importExport.exportFailed', 'Export fehlgeschlagen')
       );
     } finally {
       setIsExporting(false);
diff --git a/frontend/src/components/mail/SignatureManager.tsx b/frontend/src/components/mail/SignatureManager.tsx
index 8b25a57..019373f 100644
--- a/frontend/src/components/mail/SignatureManager.tsx
+++ b/frontend/src/components/mail/SignatureManager.tsx
@@ -3,6 +3,7 @@
  * Supports placeholder variables for user/tenant data.
  */
 
+import { asError } from '@/utils/errorTypes';
 import DOMPurify from 'dompurify';
 import React, { useState, useEffect, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
@@ -70,8 +71,8 @@ export function SignatureManager() {
         setSignatures(data);
         setError(null);
       })
-      .catch((err: any) => {
-        setError(err?.message || err?.detail || (typeof err === 'string' ? err : 'Failed to load signatures'));
+      .catch((err: unknown) => { const errObj = asError(err);
+        setError(errObj?.message || errObj?.detail || (typeof errObj === 'string' ? errObj : 'Failed to load signatures'));
       })
       .finally(() => setLoading(false));
   }, []);
@@ -103,8 +104,8 @@ export function SignatureManager() {
         toast.success(t('mail.signatureCreated'));
       }
       setShowForm(false);
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || (typeof err === 'string' ? err : 'Save failed'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || (typeof errObj === 'string' ? errObj : 'Save failed'));
     } finally {
       setSaving(false);
     }
@@ -117,8 +118,8 @@ export function SignatureManager() {
       setSignatures((prev) => prev.filter((s) => s.id !== deleteTarget.id));
       toast.success(t('mail.signatureDeleted'));
       setDeleteTarget(null);
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || (typeof err === 'string' ? err : 'Delete failed'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || (typeof errObj === 'string' ? errObj : 'Delete failed'));
     }
   }, [deleteTarget, toast, t]);
 
diff --git a/frontend/src/components/shared/CsvImportDialog.tsx b/frontend/src/components/shared/CsvImportDialog.tsx
index ab6daa9..e190e1e 100644
--- a/frontend/src/components/shared/CsvImportDialog.tsx
+++ b/frontend/src/components/shared/CsvImportDialog.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useRef, useCallback } from 'react';
 import { Modal } from '@/components/ui/Modal';
 import { Button } from '@/components/ui/Button';
@@ -74,8 +75,8 @@ export function CsvImportDialog({ open, onClose, onSuccess }: CsvImportDialogPro
       setError(null);
       onSuccess?.();
       onClose();
-    } catch (err: any) {
-      toast.error(err.message || 'Import fehlgeschlagen.');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Import fehlgeschlagen.');
     } finally {
       setImporting(false);
     }
diff --git a/frontend/src/components/tasks/TaskBoard.tsx b/frontend/src/components/tasks/TaskBoard.tsx
index 8836bb3..62a7495 100644
--- a/frontend/src/components/tasks/TaskBoard.tsx
+++ b/frontend/src/components/tasks/TaskBoard.tsx
@@ -6,7 +6,7 @@ import React from 'react';
 import { useTranslation } from 'react-i18next';
 import { Badge } from '@/components/ui/Badge';
 import { Card } from '@/components/ui/Card';
-import { useTasks, type Task, type TaskStatus } from '@/api/tasks';
+import { useTasks, type Task, type TaskStatus, type TaskFilter } from '@/api/tasks';
 import { Clock, AlertCircle, CheckCircle2, Loader2 } from 'lucide-react';
 
 const STATUS_COLUMNS: TaskStatus[] = ['open', 'in_progress', 'review', 'blocked', 'done', 'cancelled'];
@@ -92,14 +92,7 @@ function TaskCard({ task, onSelect }: TaskCardProps) {
 }
 
 interface TaskBoardProps {
-  filter?: {
-    entity_type?: string;
-    entity_id?: string;
-    assignee_type?: string;
-    assignee_id?: string;
-    parent_task_id?: string;
-    task_type?: string;
-  };
+  filter?: TaskFilter;
   onSelectTask?: (task: Task) => void;
 }
 
diff --git a/frontend/src/components/tasks/TaskDetail.tsx b/frontend/src/components/tasks/TaskDetail.tsx
index 8eebec1..ca91f76 100644
--- a/frontend/src/components/tasks/TaskDetail.tsx
+++ b/frontend/src/components/tasks/TaskDetail.tsx
@@ -169,13 +169,8 @@ export function TaskDetail({ taskId, onClose }: TaskDetailProps) {
             value={task.status}
             onChange={(e) => handleStatusChange(e.target.value as TaskStatus)}
             className="w-48"
-          >
-            {STATUS_OPTIONS.map((s) => (
-              <option key={s} value={s}>
-                {statusLabel(t, s)}
-              </option>
-            ))}
-          </Select>
+            options={STATUS_OPTIONS.map((s) => ({ value: s, label: statusLabel(t, s) }))}
+          />
         </div>
 
         {/* Assignee */}
@@ -189,13 +184,8 @@ export function TaskDetail({ taskId, onClose }: TaskDetailProps) {
               value={assigneeType}
               onChange={(e) => setAssigneeType(e.target.value as AssigneeType)}
               className="w-32"
-            >
-              {ASSIGNEE_TYPES.map((at) => (
-                <option key={at} value={at}>
-                  {t(`tasks.assigneeType${at.charAt(0).toUpperCase() + at.slice(1)}`)}
-                </option>
-              ))}
-            </Select>
+              options={ASSIGNEE_TYPES.map((at) => ({ value: at, label: t(`tasks.assigneeType${at.charAt(0).toUpperCase() + at.slice(1)}`) }))}
+            />
           </div>
           <div>
             <label htmlFor="assignee-id" className="block text-sm font-medium text-gray-700">
diff --git a/frontend/src/components/window/AiChatPanel.tsx b/frontend/src/components/window/AiChatPanel.tsx
index a3c075f..f69740f 100644
--- a/frontend/src/components/window/AiChatPanel.tsx
+++ b/frontend/src/components/window/AiChatPanel.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useRef, useEffect, useCallback } from 'react';
 import { Sparkles, Send } from 'lucide-react';
 import {
@@ -96,8 +97,8 @@ export function AiChatPanel({ windowTitle, windowType }: AiChatPanelProps) {
           setError(event.content || 'Ein Fehler ist aufgetreten');
         }
       }
-    } catch (e: any) {
-      setError(e?.message || 'KI Chat nicht verfügbar');
+    } catch (e: unknown) { const errObj = asError(e);
+      setError(errObj?.message || 'KI Chat nicht verfügbar');
     } finally {
       setIsStreaming(false);
     }
diff --git a/frontend/src/components/workflows/WorkflowEditor.tsx b/frontend/src/components/workflows/WorkflowEditor.tsx
index 4d45163..1a24f9f 100644
--- a/frontend/src/components/workflows/WorkflowEditor.tsx
+++ b/frontend/src/components/workflows/WorkflowEditor.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect } from 'react';
 // TODO: P2-F21 — Replace hardcoded triggerEventOptions with backend config
 import { useTranslation } from 'react-i18next';
@@ -166,17 +167,17 @@ export function WorkflowEditor({ open, workflow, onClose }: WorkflowEditorProps)
         toast.success('Workflow erstellt');
       }
       onClose();
-    } catch (err: any) {
+    } catch (err: unknown) { const errObj = asError(err);
       // Show detailed validation errors from backend (422)
-      if (err.validationErrors) {
-        const details = Object.entries(err.validationErrors)
+      if (errObj.validationErrors) {
+        const details = Object.entries(errObj.validationErrors)
           .map(([field, msgs]) => `${field}: ${(msgs as string[]).join(', ')}`)
           .join('; ');
         toast.error(`Validierungsfehler: ${details}`);
-      } else if (err.detail) {
-        toast.error(err.detail);
+      } else if (errObj.detail) {
+        toast.error(errObj.detail);
       } else {
-        toast.error(err.message || 'Fehler beim Speichern');
+        toast.error(errObj.message || 'Fehler beim Speichern');
       }
     }
   };
diff --git a/frontend/src/components/workflows/WorkflowInstanceDetail.tsx b/frontend/src/components/workflows/WorkflowInstanceDetail.tsx
index b5da4e0..a0fda36 100644
--- a/frontend/src/components/workflows/WorkflowInstanceDetail.tsx
+++ b/frontend/src/components/workflows/WorkflowInstanceDetail.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import {
   useWorkflowInstance,
@@ -95,8 +96,8 @@ export function WorkflowInstanceDetail({
       );
       setComment('');
       setShowCommentField(null);
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler bei der Aktion');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler bei der Aktion');
     }
   };
 
@@ -105,8 +106,8 @@ export function WorkflowInstanceDetail({
     try {
       await cancelMutation.mutateAsync(instance.id);
       toast.success('Instanz abgebrochen');
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Abbrechen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Abbrechen');
     }
   };
 
diff --git a/frontend/src/pages/AISettings.tsx b/frontend/src/pages/AISettings.tsx
index ef09808..1caf9b2 100644
--- a/frontend/src/pages/AISettings.tsx
+++ b/frontend/src/pages/AISettings.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect } from 'react';
 import { Tabs } from '@/components/shared/Tabs';
 import {
@@ -18,7 +19,7 @@ function ProviderTab() {
   const [form, setForm] = useState({ name: '', provider_type: 'openai', api_key: '', base_url: '', is_default: false });
 
   const load = async () => {
-    try { setProviders(await fetchProviders()); } catch (e: any) { setError(e?.message); } finally { setLoading(false); }
+    try { setProviders(await fetchProviders()); } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); } finally { setLoading(false); }
   };
   useEffect(() => { load(); }, []);
 
@@ -27,7 +28,7 @@ function ProviderTab() {
       if (editId) { await updateProvider(editId, form); } else { await createProvider(form); }
       setShowForm(false); setEditId(null); setForm({ name: '', provider_type: 'openai', api_key: '', base_url: '', is_default: false });
       await load();
-    } catch (e: any) { setError(e?.message); }
+    } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); }
   };
 
   const handleEdit = (p: AIProvider) => {
@@ -37,7 +38,7 @@ function ProviderTab() {
 
   const handleDelete = async (id: string) => {
     if (!confirm('Anbieter wirklich löschen?')) return;
-    try { await deleteProvider(id); await load(); } catch (e: any) { setError(e?.message); }
+    try { await deleteProvider(id); await load(); } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); }
   };
 
   if (loading) return <div className="p-4">Laden...</div>;
@@ -102,7 +103,7 @@ function PresetTab() {
   const [form, setForm] = useState({ name: '', model_id: '', provider_id: '', temperature: 0.7, max_tokens: 2048, top_p: 1.0, system_prompt: '' });
 
   const load = async () => {
-    try { setPresets(await fetchPresets()); setProviders(await fetchProviders()); } catch (e: any) { setError(e?.message); } finally { setLoading(false); }
+    try { setPresets(await fetchPresets()); setProviders(await fetchProviders()); } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); } finally { setLoading(false); }
   };
   useEffect(() => { load(); }, []);
 
@@ -112,7 +113,7 @@ function PresetTab() {
       if (editId) { await updatePreset(editId, data); } else { await createPreset(data); }
       setShowForm(false); setEditId(null); setForm({ name: '', model_id: '', provider_id: '', temperature: 0.7, max_tokens: 2048, top_p: 1.0, system_prompt: '' });
       await load();
-    } catch (e: any) { setError(e?.message); }
+    } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); }
   };
 
   const handleEdit = (p: AIPreset) => {
@@ -122,7 +123,7 @@ function PresetTab() {
 
   const handleDelete = async (id: string) => {
     if (!confirm('Preset löschen?')) return;
-    try { await deletePreset(id); await load(); } catch (e: any) { setError(e?.message); }
+    try { await deletePreset(id); await load(); } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); }
   };
 
   if (loading) return <div className="p-4">Laden...</div>;
@@ -184,7 +185,7 @@ function AgentTab() {
   const [form, setForm] = useState({ name: '', description: '', system_prompt: '', preset_id: '', tool_ids: [] as string[] });
 
   const load = async () => {
-    try { setAgents(await fetchAgents()); setPresets(await fetchPresets()); setTools(await fetchTools()); } catch (e: any) { setError(e?.message); } finally { setLoading(false); }
+    try { setAgents(await fetchAgents()); setPresets(await fetchPresets()); setTools(await fetchTools()); } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); } finally { setLoading(false); }
   };
   useEffect(() => { load(); }, []);
 
@@ -194,7 +195,7 @@ function AgentTab() {
       if (editId) { await updateAgent(editId, data); } else { await createAgent(data); }
       setShowForm(false); setEditId(null); setForm({ name: '', description: '', system_prompt: '', preset_id: '', tool_ids: [] });
       await load();
-    } catch (e: any) { setError(e?.message); }
+    } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); }
   };
 
   const handleEdit = (a: AIAgent) => {
@@ -204,7 +205,7 @@ function AgentTab() {
 
   const handleDelete = async (id: string) => {
     if (!confirm('Agent löschen?')) return;
-    try { await deleteAgent(id); await load(); } catch (e: any) { setError(e?.message); }
+    try { await deleteAgent(id); await load(); } catch (e: unknown) { const errObj = asError(e); setError(errObj?.message || null); }
   };
 
   const toggleTool = (toolName: string) => {
diff --git a/frontend/src/pages/AgentDashboard.tsx b/frontend/src/pages/AgentDashboard.tsx
index 1d3f373..b34baeb 100644
--- a/frontend/src/pages/AgentDashboard.tsx
+++ b/frontend/src/pages/AgentDashboard.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 // TODO: P2-F25 — Replace hardcoded commonModels with /ai/providers API
 import { useTranslation } from 'react-i18next';
@@ -432,8 +433,8 @@ function VersionHistoryModal({
     try {
       await restoreMutation.mutateAsync({ id: agentId, versionId });
       toast.success(t('agent.versionRestored'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -510,8 +511,8 @@ export function AgentDashboardPage() {
       }
       setShowForm(false);
       setEditingAgent(undefined);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -521,8 +522,8 @@ export function AgentDashboardPage() {
       await deleteMutation.mutateAsync(confirmDelete.id);
       toast.success(t('agent.deleted'));
       setConfirmDelete(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -530,8 +531,8 @@ export function AgentDashboardPage() {
     try {
       await executeMutation.mutateAsync(id);
       toast.success(t('agent.executed'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -539,8 +540,8 @@ export function AgentDashboardPage() {
     try {
       await testRunMutation.mutateAsync(id);
       toast.success(t('agent.testRunSuccess'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -554,8 +555,8 @@ export function AgentDashboardPage() {
       });
       toast.success(t('agent.messageSent'));
       setChatMessage('');
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/AutomationDashboard.tsx b/frontend/src/pages/AutomationDashboard.tsx
index 60b7c81..277e7bd 100644
--- a/frontend/src/pages/AutomationDashboard.tsx
+++ b/frontend/src/pages/AutomationDashboard.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
@@ -474,8 +475,8 @@ function VersionHistoryModal({
     try {
       await restoreMutation.mutateAsync({ id: automationId, versionId });
       toast.success(t('automation.versionRestored'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -548,8 +549,8 @@ export function AutomationDashboardPage() {
       }
       setShowForm(false);
       setEditingAutomation(undefined);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -559,8 +560,8 @@ export function AutomationDashboardPage() {
       await deleteMutation.mutateAsync(confirmDelete.id);
       toast.success(t('automation.deleted'));
       setConfirmDelete(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -568,8 +569,8 @@ export function AutomationDashboardPage() {
     try {
       await executeMutation.mutateAsync(id);
       toast.success(t('automation.executed'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -577,8 +578,8 @@ export function AutomationDashboardPage() {
     try {
       await dryRunMutation.mutateAsync(id);
       toast.success(t('automation.dryRunSuccess'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/AutomationSettings.tsx b/frontend/src/pages/AutomationSettings.tsx
index d9c789b..fc99b10 100644
--- a/frontend/src/pages/AutomationSettings.tsx
+++ b/frontend/src/pages/AutomationSettings.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
@@ -55,8 +56,8 @@ export function AutomationSettingsPage() {
     try {
       await updateMutation.mutateAsync(form);
       toast.success(t('automation.settingsSaved'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -92,8 +93,8 @@ export function AutomationSettingsPage() {
       setShowMiniAppForm(false);
       setMiniAppForm({ app_id: '', name: '', icon: 'AppWindow', description: '', render_schema: '{}' });
       refetchMiniapps();
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -102,8 +103,8 @@ export function AutomationSettingsPage() {
       await deleteMiniAppMutation.mutateAsync(appId);
       toast.success(t('automation.miniAppDeleted'));
       refetchMiniapps();
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/Communication.tsx b/frontend/src/pages/Communication.tsx
index 38b64bd..5056cbb 100644
--- a/frontend/src/pages/Communication.tsx
+++ b/frontend/src/pages/Communication.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect, useRef, useCallback, useMemo } from 'react';
 import clsx from 'clsx';
 import ReactMarkdown from 'react-markdown';
@@ -406,8 +407,8 @@ function ChatWindow({ convId, category, onBack }: ChatWindowProps) {
         const msg = await sendMessage(convId, content);
         setMessages(prev => [...prev, msg]);
       }
-    } catch (e: any) {
-      setError(e?.message || 'Senden fehlgeschlagen');
+    } catch (e: unknown) { const errObj = asError(e);
+      setError(errObj?.message || 'Senden fehlgeschlagen');
     } finally {
       setSending(false);
     }
@@ -428,7 +429,7 @@ function ChatWindow({ convId, category, onBack }: ChatWindowProps) {
         is_sidebar: false,
       });
       setAiSessionId(r.data.id);
-    } catch (e: any) {
+    } catch (e: unknown) { const errObj = asError(e);
       setError('KI Session konnte nicht gestartet werden');
     }
   };
diff --git a/frontend/src/pages/CustomFields.tsx b/frontend/src/pages/CustomFields.tsx
index 608a83a..3e6ae6b 100644
--- a/frontend/src/pages/CustomFields.tsx
+++ b/frontend/src/pages/CustomFields.tsx
@@ -4,6 +4,7 @@
  * Manage custom field definitions per entity (contact/company).
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useMemo, useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Card } from '@/components/ui/Card';
@@ -223,8 +224,8 @@ export function CustomFieldsPage() {
         await updateMutation.mutateAsync({ id: editingId!, data: updateData });
         toast.success(t('customFields.updated', 'Feld aktualisiert'));
         closeFormModal();
-      } catch (err: any) {
-        setFormError(err.message || 'Fehler beim Aktualisieren');
+      } catch (err: unknown) { const errObj = asError(err);
+        setFormError(errObj.message || 'Fehler beim Aktualisieren');
       }
     } else {
       const createData: CustomFieldDefinitionCreate = {
@@ -241,8 +242,8 @@ export function CustomFieldsPage() {
         await createMutation.mutateAsync(createData);
         toast.success(t('customFields.created', 'Feld erstellt'));
         closeFormModal();
-      } catch (err: any) {
-        setFormError(err.message || 'Fehler beim Erstellen');
+      } catch (err: unknown) { const errObj = asError(err);
+        setFormError(errObj.message || 'Fehler beim Erstellen');
       }
     }
   };
@@ -253,8 +254,8 @@ export function CustomFieldsPage() {
       await deleteMutation.mutateAsync(deleteTarget.id);
       toast.success(t('customFields.deleted', 'Feld gelöscht'));
       setDeleteTarget(null);
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Löschen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Löschen');
       setDeleteTarget(null);
     }
   };
diff --git a/frontend/src/pages/Login.tsx b/frontend/src/pages/Login.tsx
index 9b4a033..f6acfce 100644
--- a/frontend/src/pages/Login.tsx
+++ b/frontend/src/pages/Login.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useNavigate, Link } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
@@ -38,8 +39,8 @@ export function LoginPage() {
       await loginMutation.mutateAsync(data);
       addToast({ type: 'success', message: t('auth.login') + ' erfolgreich' });
       navigate('/start');
-    } catch (error: any) {
-      const msg = error.message || t('auth.loginFailed');
+    } catch (error: unknown) { const errObj = asError(error);
+      const msg = errObj.message || t('auth.loginFailed');
       setSubmitError(msg);
       addToast({ type: 'error', message: msg });
     }
diff --git a/frontend/src/pages/Mail.tsx b/frontend/src/pages/Mail.tsx
index 15b4ab9..d7e8fdc 100644
--- a/frontend/src/pages/Mail.tsx
+++ b/frontend/src/pages/Mail.tsx
@@ -4,6 +4,7 @@
  * Account selection is integrated into the folder tree (left pane).
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect, useCallback, useRef, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Link } from 'react-router-dom';
@@ -778,8 +779,8 @@ export function MailPage() {
               await loadMails();
               toast.success(t('mail.syncSuccess'));
             }
-          } catch (err: any) {
-            const msg = err?.message || err?.detail || (typeof err === 'string' ? err : 'Sync failed');
+          } catch (err: unknown) { const errObj = asError(err);
+            const msg = errObj?.message || errObj?.detail || (typeof errObj === 'string' ? errObj : 'Sync failed');
             toast.error(msg);
           } finally {
             setIsSyncing(false);
diff --git a/frontend/src/pages/MailSettings.tsx b/frontend/src/pages/MailSettings.tsx
index 048d74b..a6a0094 100644
--- a/frontend/src/pages/MailSettings.tsx
+++ b/frontend/src/pages/MailSettings.tsx
@@ -2,6 +2,7 @@
  * Mail settings page — signatures, rules, labels, PGP, vacation responder.
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useCallback, useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useSearchParams } from 'react-router-dom';
@@ -77,8 +78,8 @@ export function MailSettingsPage() {
       if (accs.length > 0) {
         setSelectedAccountId((prev) => prev || accs[0].id);
       }
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Failed to load accounts');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Failed to load accounts');
     }
     setLoading(false);
   // eslint-disable-next-line react-hooks/exhaustive-deps
@@ -93,8 +94,8 @@ export function MailSettingsPage() {
       toast.success(t('mail.accountCreated'));
       setShowAddAccount(false);
       resetAccount({ email: '', display_name: '', username: '', imap_host: '', imap_port: 993, smtp_host: '', smtp_port: 587, password: '', is_shared: false });
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Save failed');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Save failed');
     }
   }, [toast, t, resetAccount]);
 
@@ -107,8 +108,8 @@ export function MailSettingsPage() {
       } else {
         toast.error(result.message);
       }
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Connection test failed');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Connection test failed');
     } finally {
       setTesting(null);
     }
@@ -123,8 +124,8 @@ export function MailSettingsPage() {
       } else {
         toast.success(t('mail.syncSuccess'));
       }
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Sync failed');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Sync failed');
     } finally {
       setSyncing(null);
     }
@@ -136,8 +137,8 @@ export function MailSettingsPage() {
       await deleteAccount(accountId);
       setAccounts((prev) => prev.filter((a) => a.id !== accountId));
       toast.success(t('mail.accountDeleted'));
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Delete failed');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Delete failed');
     }
   }, [toast, t]);
 
@@ -147,8 +148,8 @@ export function MailSettingsPage() {
       setAccounts((prev) => prev.map((a) => (a.id === accountId ? updated : a)));
       setEditingDisplayName(null);
       toast.success(t('common.saved'));
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Save failed');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Save failed');
     }
   }, [displayNameValue, toast, t]);
 
@@ -191,8 +192,8 @@ export function MailSettingsPage() {
       setAccounts((prev) => prev.map((a) => (a.id === accountId ? updated : a)));
       setFolderMappingEdit(null);
       toast.success(t('common.saved'));
-    } catch (err: any) {
-      toast.error(err?.message || err?.detail || 'Save failed');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || errObj?.detail || 'Save failed');
     } finally {
       setSavingMapping(false);
     }
diff --git a/frontend/src/pages/Reports.tsx b/frontend/src/pages/Reports.tsx
index e391e22..ed6a0e1 100644
--- a/frontend/src/pages/Reports.tsx
+++ b/frontend/src/pages/Reports.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
@@ -126,8 +127,8 @@ export function ReportsPage() {
         });
         toast.success(t('reports.templateUpdated', 'Template updated successfully'));
       }
-    } catch (err: any) {
-      toast.error(err?.message || t('reports.saveFailed', 'Failed to save template'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || t('reports.saveFailed', 'Failed to save template'));
     }
   };
 
@@ -141,8 +142,8 @@ export function ReportsPage() {
         setEditorContent('');
       }
       toast.success(t('reports.templateDeleted', 'Template deleted'));
-    } catch (err: any) {
-      toast.error(err?.message || t('reports.deleteFailed', 'Failed to delete template'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || t('reports.deleteFailed', 'Failed to delete template'));
     }
   };
 
@@ -174,8 +175,8 @@ export function ReportsPage() {
         ...prev,
       ]);
       toast.success(t('reports.generated', 'Report generated successfully'));
-    } catch (err: any) {
-      toast.error(err?.message || t('reports.generateFailed', 'Failed to generate report'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || t('reports.generateFailed', 'Failed to generate report'));
     }
   };
 
@@ -207,8 +208,8 @@ export function ReportsPage() {
         ...prev,
       ]);
       toast.success(t('reports.generated', 'Report generated successfully'));
-    } catch (err: any) {
-      toast.error(err?.message || t('reports.generateFailed', 'Failed to generate report'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj?.message || t('reports.generateFailed', 'Failed to generate report'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsCurrencies.tsx b/frontend/src/pages/SettingsCurrencies.tsx
index 2394235..ac7b27c 100644
--- a/frontend/src/pages/SettingsCurrencies.tsx
+++ b/frontend/src/pages/SettingsCurrencies.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -47,8 +48,8 @@ export function SettingsCurrenciesPage() {
     try {
       const data = await apiGet<{ items: Currency[]; total: number }>('/currencies');
       setCurrencies(data.items);
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     } finally {
       setLoading(false);
     }
@@ -67,8 +68,8 @@ export function SettingsCurrenciesPage() {
       setEditing(null);
       reset({ code: '', name: '', symbol: '', is_default: false });
       await fetchCurrencies();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
@@ -77,8 +78,8 @@ export function SettingsCurrenciesPage() {
     try {
       await apiDelete(`/currencies/${id}`);
       await fetchCurrencies();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsFirmendaten.tsx b/frontend/src/pages/SettingsFirmendaten.tsx
index 28560dd..9392e87 100644
--- a/frontend/src/pages/SettingsFirmendaten.tsx
+++ b/frontend/src/pages/SettingsFirmendaten.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -111,8 +112,8 @@ export function SettingsFirmendatenPage() {
       if (!payload.default_tax_id) payload.default_tax_id = null as any;
       await updateMutation.mutateAsync(payload);
       toast.success(t('systemSettings.saved'));
-    } catch (err: any) {
-      toast.error(err.message || t('systemSettings.saveFailed'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('systemSettings.saveFailed'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsGroups.tsx b/frontend/src/pages/SettingsGroups.tsx
index e9a51d4..6a363e7 100644
--- a/frontend/src/pages/SettingsGroups.tsx
+++ b/frontend/src/pages/SettingsGroups.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -144,8 +145,8 @@ export function SettingsGroupsPage() {
       setNewGroupPermissions({});
       setNewGroupDenied([]);
       setCreateOpen(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -190,8 +191,8 @@ export function SettingsGroupsPage() {
       });
       toast.success(t('settings.groupUpdated', 'Gruppe aktualisiert'));
       setEditingGroup(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -201,8 +202,8 @@ export function SettingsGroupsPage() {
       await deleteGroupMutation.mutateAsync(confirmDelete.id);
       toast.success(t('settings.groupDeleted', 'Gruppe gelöscht'));
       setConfirmDelete(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -501,8 +502,8 @@ function EditGroupContent({
       await addMemberMutation.mutateAsync({ groupId, userId: memberSearchUserId });
       toast.success(t('settings.memberAdded', 'Mitglied hinzugefügt'));
       setMemberSearchUserId('');
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -511,8 +512,8 @@ function EditGroupContent({
     try {
       await removeMemberMutation.mutateAsync({ groupId, userId });
       toast.success(t('settings.memberRemoved', 'Mitglied entfernt'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsMenuOrder.tsx b/frontend/src/pages/SettingsMenuOrder.tsx
index a7e0b08..df11ffc 100644
--- a/frontend/src/pages/SettingsMenuOrder.tsx
+++ b/frontend/src/pages/SettingsMenuOrder.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect, useMemo, useCallback } from 'react';
 // TODO: P2-F23 — Replace hardcoded DEFAULT_ORDER with backend config
 import { useTranslation } from 'react-i18next';
@@ -162,8 +163,8 @@ export function SettingsMenuOrderPage() {
       const order = items.map((item) => item.id);
       await updateMutation.mutateAsync(order);
       toast.success(t('settings.saved', 'Gespeichert'));
-    } catch (err: any) {
-      toast.error(err.message || t('settings.saveFailed', 'Speichern fehlgeschlagen'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('settings.saveFailed', 'Speichern fehlgeschlagen'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsNotifications.tsx b/frontend/src/pages/SettingsNotifications.tsx
index 5cf011b..b810e1a 100644
--- a/frontend/src/pages/SettingsNotifications.tsx
+++ b/frontend/src/pages/SettingsNotifications.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useToast } from '@/components/ui/Toast';
@@ -42,8 +43,8 @@ export function SettingsNotificationsPage() {
         onSuccess: () => {
           toast.success(t('notifications.saved'));
         },
-        onError: (err: any) => {
-          toast.error(err.message || t('common.error'));
+        onError: (err: unknown) => { const errObj = asError(err);
+          toast.error(errObj.message || t('common.error'));
         },
       }
     );
diff --git a/frontend/src/pages/SettingsPlugins.tsx b/frontend/src/pages/SettingsPlugins.tsx
index 0b3f2d3..3d1931d 100644
--- a/frontend/src/pages/SettingsPlugins.tsx
+++ b/frontend/src/pages/SettingsPlugins.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useRef } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
@@ -79,8 +80,8 @@ function InstallPluginSection() {
       if (fileInputRef.current) {
         fileInputRef.current.value = '';
       }
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -93,8 +94,8 @@ function InstallPluginSection() {
       await installUrlMutation.mutateAsync(url.trim());
       toast.success(t('settings.pluginUrlInstalledSuccess'));
       setUrl('');
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -188,8 +189,8 @@ export function SettingsPluginsPage() {
     try {
       await installMutation.mutateAsync(plugin.name);
       toast.success(t('settings.pluginInstalledSuccess'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -197,8 +198,8 @@ export function SettingsPluginsPage() {
     try {
       await activateMutation.mutateAsync(plugin.name);
       toast.success(t('settings.pluginActivatedSuccess'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -206,8 +207,8 @@ export function SettingsPluginsPage() {
     try {
       await deactivateMutation.mutateAsync(plugin.name);
       toast.success(t('settings.pluginDeactivatedSuccess'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -218,8 +219,8 @@ export function SettingsPluginsPage() {
       toast.success(t('settings.pluginUninstalledSuccess'));
       setConfirmUninstall(null);
       setConfirmRemoveData(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsProfile.tsx b/frontend/src/pages/SettingsProfile.tsx
index 906b0e3..448449e 100644
--- a/frontend/src/pages/SettingsProfile.tsx
+++ b/frontend/src/pages/SettingsProfile.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useAuthStore } from '@/store/authStore';
@@ -33,8 +34,8 @@ export function SettingsProfilePage() {
       });
       toast.success(t('settings.profileSaved'));
       setProfileDirty(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -58,8 +59,8 @@ export function SettingsProfilePage() {
       setNewPassword('');
       setConfirmPassword('');
       setPasswordDirty(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsRechte.tsx b/frontend/src/pages/SettingsRechte.tsx
index d88ad57..2a5e9ea 100644
--- a/frontend/src/pages/SettingsRechte.tsx
+++ b/frontend/src/pages/SettingsRechte.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useMemo } from 'react';
 // TODO: P2-T19 — Replace hardcoded PermissionLevelBadge/PrincipalTypeBadge with i18n
 import { useTranslation } from 'react-i18next';
@@ -140,8 +141,8 @@ function FreigabenTab() {
       toast.success('Berechtigung gelöscht');
       setConfirmDelete(null);
       refetchPerms();
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Löschen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Löschen');
     } finally {
       setDeleting(false);
     }
diff --git a/frontend/src/pages/SettingsRoles.tsx b/frontend/src/pages/SettingsRoles.tsx
index 026ab5f..c08f9d4 100644
--- a/frontend/src/pages/SettingsRoles.tsx
+++ b/frontend/src/pages/SettingsRoles.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -143,8 +144,8 @@ export function SettingsRolesPage() {
       setNewRolePermissions({});
       setNewRoleDenied([]);
       setCreateOpen(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -201,8 +202,8 @@ export function SettingsRolesPage() {
       });
       toast.success(t('settings.roleUpdated'));
       setEditingRole(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -212,8 +213,8 @@ export function SettingsRolesPage() {
       await deleteRoleMutation.mutateAsync(confirmDelete.id);
       toast.success(t('settings.roleDeleted'));
       setConfirmDelete(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsSequences.tsx b/frontend/src/pages/SettingsSequences.tsx
index 4661eda..013383b 100644
--- a/frontend/src/pages/SettingsSequences.tsx
+++ b/frontend/src/pages/SettingsSequences.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -46,8 +47,8 @@ export function SettingsSequencesPage() {
     try {
       const data = await apiGet<{ items: Sequence[]; total: number }>('/sequences');
       setSequences(data.items);
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     } finally {
       setLoading(false);
     }
@@ -66,8 +67,8 @@ export function SettingsSequencesPage() {
       setEditing(null);
       reset({ name: '', prefix: '', padding: 4 });
       await fetchSequences();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
@@ -76,8 +77,8 @@ export function SettingsSequencesPage() {
     try {
       await apiDelete(`/sequences/${id}`);
       await fetchSequences();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsStammdaten.tsx b/frontend/src/pages/SettingsStammdaten.tsx
index 70afb43..c5a0494 100644
--- a/frontend/src/pages/SettingsStammdaten.tsx
+++ b/frontend/src/pages/SettingsStammdaten.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useEffect, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { SettingsFirmendatenPage } from './SettingsFirmendaten';
@@ -87,8 +88,8 @@ function AdressenTab() {
           label: a.label || '',
         }))
       );
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Laden der Adressen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Laden der Adressen');
     } finally {
       setLoading(false);
     }
@@ -113,8 +114,8 @@ function AdressenTab() {
       await apiDelete(`/addresses/${id}`);
       setAddresses(addresses.filter(a => a.id !== id));
       toast.success('Adresse gelöscht');
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Löschen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Löschen');
     }
   };
 
@@ -151,8 +152,8 @@ function AdressenTab() {
       setShowForm(false);
       setEditing(null);
       await fetchAddresses();
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Speichern');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Speichern');
     }
   };
 
@@ -284,8 +285,8 @@ function KontenTab() {
           defaultTax: a.default_tax || '',
         }))
       );
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Laden der Konten');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Laden der Konten');
     } finally {
       setLoading(false);
     }
@@ -310,8 +311,8 @@ function KontenTab() {
       await apiDelete(`/bank-accounts/${id}`);
       setAccounts(accounts.filter(a => a.id !== id));
       toast.success('Konto gelöscht');
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Löschen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Löschen');
     }
   };
 
@@ -337,8 +338,8 @@ function KontenTab() {
       setShowForm(false);
       setEditing(null);
       await fetchAccounts();
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Speichern');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Speichern');
     }
   };
 
diff --git a/frontend/src/pages/SettingsTaxes.tsx b/frontend/src/pages/SettingsTaxes.tsx
index fc1377a..5cdec2c 100644
--- a/frontend/src/pages/SettingsTaxes.tsx
+++ b/frontend/src/pages/SettingsTaxes.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useForm } from 'react-hook-form';
@@ -47,8 +48,8 @@ export function SettingsTaxesPage() {
     try {
       const data = await apiGet<{ items: TaxRate[]; total: number }>('/taxes');
       setTaxes(data.items);
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     } finally {
       setLoading(false);
     }
@@ -68,8 +69,8 @@ export function SettingsTaxesPage() {
       setEditing(null);
       reset({ name: '', rate: 0, is_default: false, country: '' });
       await fetchTaxes();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
@@ -78,8 +79,8 @@ export function SettingsTaxesPage() {
     try {
       await apiDelete(`/taxes/${id}`);
       await fetchTaxes();
-    } catch (err: any) {
-      setError(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      setError(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsUsers.tsx b/frontend/src/pages/SettingsUsers.tsx
index 844e09b..6bd4304 100644
--- a/frontend/src/pages/SettingsUsers.tsx
+++ b/frontend/src/pages/SettingsUsers.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useMemo } from 'react';
 // TODO: P2-F22 — Replace hardcoded LEGACY_ROLES with /roles API
 import { useTranslation } from 'react-i18next';
@@ -107,8 +108,8 @@ export function SettingsUsersPage() {
       toast.success(t('settings.userInvited'));
       reset({ name: '', email: '', password: '', role_id: '' });
       setInviteOpen(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -124,8 +125,8 @@ export function SettingsUsersPage() {
       }
       await updateUserMutation.mutateAsync({ id: userId, data });
       toast.success(t('settings.assignRole') + ' — OK');
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -140,8 +141,8 @@ export function SettingsUsersPage() {
         toast.success(t('settings.userDeactivated'));
       }
       setConfirmDeactivate(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -151,8 +152,8 @@ export function SettingsUsersPage() {
       await deleteUserMutation.mutateAsync(confirmDelete.id);
       toast.success(t('settings.userDeleted'));
       setConfirmDelete(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
diff --git a/frontend/src/pages/SettingsWebhooks.tsx b/frontend/src/pages/SettingsWebhooks.tsx
index d2559c9..970afa6 100644
--- a/frontend/src/pages/SettingsWebhooks.tsx
+++ b/frontend/src/pages/SettingsWebhooks.tsx
@@ -8,6 +8,7 @@
  * - Test button sends test payload, shows result
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
@@ -377,8 +378,8 @@ export function SettingsWebhooksPage() {
               setFormModalOpen(false);
               setEditingWebhook(null);
             },
-            onError: (err: any) => {
-              setFormError(err?.message || t('webhooks.updateError', 'Fehler beim Aktualisieren'));
+            onError: (err: unknown) => { const errObj = asError(err);
+              setFormError(errObj?.message || t('webhooks.updateError', 'Fehler beim Aktualisieren'));
             },
           }
         );
@@ -387,8 +388,8 @@ export function SettingsWebhooksPage() {
           onSuccess: () => {
             setFormModalOpen(false);
           },
-          onError: (err: any) => {
-            setFormError(err?.message || t('webhooks.createError', 'Fehler beim Erstellen'));
+          onError: (err: unknown) => { const errObj = asError(err);
+            setFormError(errObj?.message || t('webhooks.createError', 'Fehler beim Erstellen'));
           },
         });
       }
@@ -418,8 +419,8 @@ export function SettingsWebhooksPage() {
           setTestResult(result);
           setTestResultModalOpen(true);
         },
-        onError: (err: any) => {
-          setTestResult({ success: false, status_code: null, error: err?.message || 'Unknown error' });
+        onError: (err: unknown) => { const errObj = asError(err);
+          setTestResult({ success: false, status_code: null, error: errObj?.message || 'Unknown error' });
           setTestResultModalOpen(true);
         },
       });
diff --git a/frontend/src/pages/Tasks.tsx b/frontend/src/pages/Tasks.tsx
index 76d6b53..9a11ef3 100644
--- a/frontend/src/pages/Tasks.tsx
+++ b/frontend/src/pages/Tasks.tsx
@@ -2,6 +2,7 @@
  * Tasks page — list with filter, create modal, detail.
  */
 
+import { asError } from '@/utils/errorTypes';
 import React, { useState, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { Button } from '@/components/ui/Button';
@@ -20,6 +21,7 @@ import {
   useUpdateTaskStatus,
   type Task,
   type TaskFilter,
+  type TaskStatus,
 } from '@/api/tasks';
 
 const STATUS_COLORS: Record<string, 'secondary' | 'info' | 'success'> = {
@@ -96,8 +98,8 @@ export function TasksPage() {
       });
       toast.success(t('tasks.created'));
       setCreateModalOpen(false);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -107,8 +109,8 @@ export function TasksPage() {
       await updateMutation.mutateAsync({ id: editingTask.id, data: formData });
       toast.success(t('tasks.updated'));
       setEditingTask(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -118,17 +120,17 @@ export function TasksPage() {
       await deleteMutation.mutateAsync(task.id);
       toast.success(t('tasks.deleted'));
       setSelectedTask(null);
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
-  const handleStatusChange = async (task: Task, newStatus: string) => {
+  const handleStatusChange = async (task: Task, newStatus: TaskStatus) => {
     try {
       await statusMutation.mutateAsync({ id: task.id, status: newStatus });
       toast.success(t('tasks.statusUpdated'));
-    } catch (err: any) {
-      toast.error(err.message || t('common.error'));
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || t('common.error'));
     }
   };
 
@@ -163,7 +165,7 @@ export function TasksPage() {
             { value: 'done', label: t('tasks.statusDone') },
           ]}
           value={filter.status || ''}
-          onChange={(e) => { setFilter(f => ({ ...f, status: e.target.value || undefined })); setPage(1); }}
+          onChange={(e) => { setFilter(f => ({ ...f, status: (e.target.value || undefined) as TaskStatus | undefined })); setPage(1); }}
           className="w-40"
         />
         <Select
diff --git a/frontend/src/pages/Workflows.tsx b/frontend/src/pages/Workflows.tsx
index 282b3ec..a299030 100644
--- a/frontend/src/pages/Workflows.tsx
+++ b/frontend/src/pages/Workflows.tsx
@@ -1,3 +1,4 @@
+import { asError } from '@/utils/errorTypes';
 import React, { useState } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
@@ -56,8 +57,8 @@ export function WorkflowsPage() {
       toast.success(
         workflow.is_active ? 'Workflow deaktiviert' : 'Workflow aktiviert'
       );
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Umschalten');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Umschalten');
     }
   };
 
@@ -67,8 +68,8 @@ export function WorkflowsPage() {
       await deleteMutation.mutateAsync(confirmDelete.id);
       toast.success('Workflow geloescht');
       setConfirmDelete(null);
-    } catch (err: any) {
-      toast.error(err.message || 'Fehler beim Loeschen');
+    } catch (err: unknown) { const errObj = asError(err);
+      toast.error(errObj.message || 'Fehler beim Loeschen');
     }
   };
 
diff --git a/frontend/src/types/automation.ts b/frontend/src/types/automation.ts
index d350dbe..43902af 100644
--- a/frontend/src/types/automation.ts
+++ b/frontend/src/types/automation.ts
@@ -86,6 +86,44 @@ export interface AgentTool {
   description: string;
 }
 
+export interface AgentToolInfo extends AgentTool {
+  id?: string;
+  category?: string;
+  required_permissions?: string[];
+}
+
+export interface AgentSkillInfo {
+  name: string;
+  description: string;
+  tools?: string[];
+  required_permissions?: string[];
+}
+
+export interface AgentRunFull extends AgentRun {
+  agent_name?: string;
+  cost?: number;
+  steps?: number;
+  error_category?: string;
+}
+
+export interface AgentDefinitionFull extends AgentDefinition {
+  llm_model?: string;
+  tool_ids?: string[];
+  skill_ids?: string[];
+  max_steps?: number;
+  max_duration_seconds?: number;
+  budget_limit_usd?: number;
+  temperature?: number;
+  max_tokens?: number;
+  trace_mode?: 'standard' | 'extended' | 'off';
+  is_active?: boolean;
+  trigger_config?: Record<string, unknown>;
+  ai_use_case_metadata?: Record<string, unknown>;
+  tools_list?: AgentToolInfo[];
+  skills_list?: AgentSkillInfo[];
+  version?: number;
+}
+
 export interface AutomationSettings {
   default_llm_model: string;
   heartbeat_default_interval: number;
diff --git a/frontend/src/utils/errorTypes.ts b/frontend/src/utils/errorTypes.ts
index 3a54f68..7079df1 100644
--- a/frontend/src/utils/errorTypes.ts
+++ b/frontend/src/utils/errorTypes.ts
@@ -9,12 +9,49 @@ export interface CategorizedError {
   field?: string;
 }
 
-export function categorizeError(error: any): CategorizedError {
-  const status = error?.status || 0;
-  if (status === 0) return { category: 'network', status: 0, message: 'Netzwerkfehler', detail: error?.message };
-  if (status === 401) return { category: 'auth', status, message: 'Nicht authentifiziert', detail: error?.detail };
-  if (status === 403) return { category: 'permission', status, message: 'Keine Berechtigung', detail: error?.detail };
-  if (status === 422) return { category: 'validation', status, message: 'Validierungsfehler', detail: error?.detail, field: error?.field };
-  if (status >= 500) return { category: 'server', status, message: 'Serverfehler', detail: error?.detail };
-  return { category: 'unknown', status, message: error?.message || 'Unbekannter Fehler', detail: error?.detail };
+export interface ErrorLike {
+  status?: number;
+  message?: string;
+  detail?: string;
+  validationErrors?: Record<string, string[]>;
+  code?: string;
+  field?: string;
+  response?: { data?: { detail?: { detail?: unknown } } };
+}
+
+/**
+ * Narrow an unknown error value to a typed error-like object.
+ * Handles strings, Error instances, and API error payloads.
+ */
+export function asError(error: unknown): ErrorLike {
+  if (typeof error === 'string') {
+    return { message: error };
+  }
+  if (error instanceof Error) {
+    return { message: error.message };
+  }
+  if (error && typeof error === 'object') {
+    const e = error as Record<string, unknown>;
+    return {
+      status: typeof e.status === 'number' ? e.status : undefined,
+      message: typeof e.message === 'string' ? e.message : undefined,
+      detail: typeof e.detail === 'string' ? e.detail : undefined,
+      validationErrors: e.validationErrors as Record<string, string[]> | undefined,
+      code: typeof e.code === 'string' ? e.code : undefined,
+      field: typeof e.field === 'string' ? e.field : undefined,
+      response: e.response as { data?: { detail?: { detail?: unknown } } } | undefined,
+    };
+  }
+  return {};
+}
+
+export function categorizeError(error: unknown): CategorizedError {
+  const e = asError(error);
+  const status = e.status || 0;
+  if (status === 0) return { category: 'network', status: 0, message: 'Netzwerkfehler', detail: e.message };
+  if (status === 401) return { category: 'auth', status, message: 'Nicht authentifiziert', detail: e.detail };
+  if (status === 403) return { category: 'permission', status, message: 'Keine Berechtigung', detail: e.detail };
+  if (status === 422) return { category: 'validation', status, message: 'Validierungsfehler', detail: e.detail, field: e.field };
+  if (status >= 500) return { category: 'server', status, message: 'Serverfehler', detail: e.detail };
+  return { category: 'unknown', status, message: e.message || 'Unbekannter Fehler', detail: e.detail };
 }