diff --git a/lib/core/network/api_error.dart b/lib/core/network/api_error.dart
index ad1d85f..b4dc4f1 100644
--- a/lib/core/network/api_error.dart
+++ b/lib/core/network/api_error.dart
@@ -4,6 +4,7 @@ import 'package:dio/dio.dart';
 enum ApiErrorCode {
   badRequest,
   unauthorized,
+  forbidden,
   notFound,
   conflict,
   unprocessableEntity,
@@ -92,6 +93,14 @@ class ApiErrorMapper {
             statusCode: status,
             cause: error,
           );
+        case 403:
+          return ApiException(
+            code: ApiErrorCode.forbidden,
+            message: message,
+            statusCode: status,
+            details: _extractDetails(data),
+            cause: error,
+          );
         case 404:
           return ApiException(
             code: ApiErrorCode.notFound,
@@ -131,24 +140,196 @@ class ApiErrorMapper {
   /// 응답 바디 혹은 Dio 예외 객체에서 사용자용 메시지를 추출한다.
   String _resolveMessage(DioException error, dynamic data) {
     if (data is Map<String, dynamic>) {
-      final message = data['message'] ?? data['error'];
-      if (message is String && message.isNotEmpty) {
-        return message;
+      final candidates = [
+        data['message'],
+        data['error_message'],
+        data['errorMessage'],
+        data['detail'],
+      ];
+      for (final candidate in candidates) {
+        if (candidate is String && candidate.trim().isNotEmpty) {
+          return candidate.trim();
+        }
       }
-    } else if (data is String && data.isNotEmpty) {
-      return data;
+      final errorNode = data['error'];
+      if (errorNode is String && errorNode.trim().isNotEmpty) {
+        return errorNode.trim();
+      }
+      if (errorNode is Map<String, dynamic>) {
+        final nested = [
+          errorNode['message'],
+          errorNode['title'],
+          errorNode['detail'],
+          errorNode['error'],
+        ];
+        for (final candidate in nested) {
+          if (candidate is String && candidate.trim().isNotEmpty) {
+            return candidate.trim();
+          }
+        }
+      }
+      final messagesNode = data['messages'];
+      if (messagesNode is Iterable) {
+        final flattened = _flattenMessages(messagesNode);
+        if (flattened != null) {
+          return flattened;
+        }
+      }
+      final errorsNode = data['errors'];
+      final flattenedErrors = _flattenMessages(errorsNode);
+      if (flattenedErrors != null) {
+        return flattenedErrors;
+      }
+    } else if (data is String && data.trim().isNotEmpty) {
+      return data.trim();
     }
-    return error.message ?? '요청 처리 중 알 수 없는 오류가 발생했습니다.';
+    return error.message?.trim() ?? '요청 처리 중 알 수 없는 오류가 발생했습니다.';
   }
 
   /// 422/409 등에서 제공되는 필드별 오류 정보를 추출한다.
   Map<String, dynamic>? _extractDetails(dynamic data) {
-    if (data is Map<String, dynamic>) {
-      final errors = data['errors'];
-      if (errors is Map<String, dynamic>) {
-        return errors;
+    if (data is! Map) {
+      return null;
+    }
+    Map<String, dynamic>? result;
+
+    void merge(dynamic node) {
+      if (node == null) {
+        return;
+      }
+      if (node is Map) {
+        if (node.isEmpty) {
+          return;
+        }
+        result ??= <String, dynamic>{};
+        node.forEach((rawKey, rawValue) {
+          final key = rawKey?.toString() ?? '';
+          if (key.isEmpty) {
+            return;
+          }
+          final values = _asList(rawValue);
+          if (values.isEmpty) {
+            return;
+          }
+          final existing = result![key];
+          if (existing == null) {
+            result![key] = values.length == 1 ? values.first : values;
+            return;
+          }
+          final merged = _asList(existing)..addAll(values);
+          result![key] = merged.length == 1 ? merged.first : merged;
+        });
+        return;
+      }
+      if (node is Iterable) {
+        final mapped = _mapFromErrors(node);
+        if (mapped != null) {
+          merge(mapped);
+        }
+        return;
+      }
+      final mapped = _mapFromErrors([node]);
+      if (mapped != null) {
+        merge(mapped);
       }
     }
-    return null;
+
+    final map = data.cast<dynamic, dynamic>();
+    merge(map['errors']);
+    merge(map['details']);
+    merge(map['context']);
+
+    final errorNode = map['error'];
+    if (errorNode is Map) {
+      merge(errorNode['errors']);
+      merge(errorNode['details']);
+      merge(errorNode['context']);
+    }
+
+    return result;
+  }
+
+  String? _flattenMessages(dynamic source) {
+    if (source == null) {
+      return null;
+    }
+    if (source is String) {
+      final trimmed = source.trim();
+      return trimmed.isEmpty ? null : trimmed;
+    }
+    if (source is Iterable) {
+      final buffer = <String>[];
+      for (final item in source) {
+        final value = _flattenMessages(item);
+        if (value != null && value.isNotEmpty) {
+          buffer.add(value);
+        }
+      }
+      if (buffer.isEmpty) {
+        return null;
+      }
+      return buffer.join('\n');
+    }
+    if (source is Map) {
+      final message =
+          source['message'] ??
+          source['detail'] ??
+          source['error'] ??
+          source['description'];
+      final flattened = _flattenMessages(message);
+      if (flattened != null) {
+        return flattened;
+      }
+      return _flattenMessages(source.values);
+    }
+    if (source is num || source is bool) {
+      return source.toString();
+    }
+    return source.toString();
+  }
+
+  Map<String, dynamic>? _mapFromErrors(Iterable<dynamic> errors) {
+    final result = <String, dynamic>{};
+    for (final entry in errors) {
+      if (entry is Map) {
+        final field = entry['field'] ?? entry['name'] ?? entry['key'];
+        final messages =
+            entry['messages'] ??
+            entry['message'] ??
+            entry['detail'] ??
+            entry['error'];
+        if (field is String) {
+          final bucket = result[field];
+          final nextMessages = _asList(messages);
+          if (bucket is List) {
+            bucket.addAll(nextMessages);
+          } else if (bucket != null) {
+            result[field] = _asList(bucket)..addAll(nextMessages);
+          } else if (nextMessages.length == 1) {
+            result[field] = nextMessages.first;
+          } else {
+            result[field] = nextMessages;
+          }
+          continue;
+        }
+      }
+      final list =
+          result.putIfAbsent('general', () => <dynamic>[]) as List<dynamic>;
+      list.add(entry);
+    }
+    return result.isEmpty ? null : result;
+  }
+
+  List<dynamic> _asList(dynamic value) {
+    if (value == null) {
+      return <dynamic>[];
+    }
+    if (value is List) {
+      return value;
+    }
+    if (value is Iterable) {
+      return value.toList();
+    }
+    return <dynamic>[value];
   }
 }
diff --git a/lib/core/network/failure.dart b/lib/core/network/failure.dart
new file mode 100644
index 0000000..9d3ba60
--- /dev/null
+++ b/lib/core/network/failure.dart
@@ -0,0 +1,448 @@
+import 'package:dio/dio.dart';
+
+import 'api_error.dart';
+
+/// 서버/네트워크 예외를 사용자 메시지와 필드 오류 형태로 정규화한 객체.
+class Failure {
+  const Failure({
+    required this.message,
+    this.code,
+    this.statusCode,
+    this.reasons = const [],
+    this.fieldErrors = const {},
+    this.raw,
+  });
+
+  /// 사용자에게 우선 노출할 기본 메시지.
+  final String message;
+
+  /// [ApiErrorCode] 또는 유사 코드.
+  final ApiErrorCode? code;
+
+  /// HTTP 상태 코드(존재하는 경우).
+  final int? statusCode;
+
+  /// 추가 설명 메시지 목록.
+  final List<String> reasons;
+
+  /// 필드별 오류 메시지 묶음.
+  final Map<String, List<String>> fieldErrors;
+
+  /// 원본 예외 객체.
+  final Object? raw;
+
+  /// 필드 오류가 존재하는지 여부.
+  bool get hasFieldErrors => fieldErrors.isNotEmpty;
+
+  /// 추가 설명이 존재하는지 여부.
+  bool get hasReasons => reasons.isNotEmpty;
+
+  /// 필드명에 해당하는 첫 번째 오류 메시지를 반환한다.
+  String? firstFieldError(String field) {
+    final messages = fieldErrors[field];
+    if (messages == null) {
+      return null;
+    }
+    for (final message in messages) {
+      final trimmed = message.trim();
+      if (trimmed.isNotEmpty) {
+        return trimmed;
+      }
+    }
+    return null;
+  }
+
+  /// 필드 오류를 줄바꿈으로 합친 문자열 맵을 반환한다.
+  Map<String, String> get fieldErrorMessages {
+    final result = <String, String>{};
+    fieldErrors.forEach((key, value) {
+      final messages = _dedupeStrings(value);
+      if (messages.isEmpty) {
+        return;
+      }
+      result[key] = messages.join('\n');
+    });
+    return result;
+  }
+
+  /// 기본 메시지와 추가 설명 및 필드 오류를 단일 문자열로 합친다.
+  String describe({String separator = '\n', bool includeFieldErrors = true}) {
+    final lines = <String>[];
+    final base = message.trim();
+    if (base.isNotEmpty) {
+      lines.add(base);
+    }
+    for (final reason in reasons) {
+      final trimmed = reason.trim();
+      if (trimmed.isEmpty) {
+        continue;
+      }
+      final duplicate = lines.any(
+        (existing) => existing.toLowerCase() == trimmed.toLowerCase(),
+      );
+      if (!duplicate) {
+        lines.add(trimmed);
+      }
+    }
+    if (includeFieldErrors && fieldErrors.isNotEmpty) {
+      fieldErrors.forEach((key, value) {
+        final first = value.firstWhere(
+          (message) => message.trim().isNotEmpty,
+          orElse: () => '',
+        );
+        final trimmed = first.trim();
+        if (trimmed.isEmpty) {
+          return;
+        }
+        final line = '$key: $trimmed';
+        final duplicate = lines.any(
+          (existing) => existing.toLowerCase() == line.toLowerCase(),
+        );
+        if (!duplicate) {
+          lines.add(line);
+        }
+      });
+    }
+    return lines.join(separator).trim();
+  }
+
+  /// 임의 객체에서 [Failure]를 생성한다.
+  static Failure from(Object error) => const FailureParser().parse(error);
+}
+
+/// [Failure] 변환을 담당하는 파서.
+class FailureParser {
+  const FailureParser();
+
+  Failure parse(Object error) {
+    if (error is Failure) {
+      return error;
+    }
+    if (error is ApiException) {
+      return _fromApiException(error);
+    }
+    if (error is DioException) {
+      final mapped = const ApiErrorMapper().map(error);
+      return _fromApiException(mapped);
+    }
+    if (error is Exception || error is Error) {
+      final message = _exceptionMessage(error);
+      return Failure(message: message, raw: error);
+    }
+    final fallback = error.toString().trim();
+    return Failure(
+      message: fallback.isEmpty ? '요청 처리 중 오류가 발생했습니다.' : fallback,
+      raw: error,
+    );
+  }
+
+  Failure _fromApiException(ApiException exception) {
+    final payload = _FailurePayload();
+    payload.consumeDetails(exception.details);
+    payload.consumeResponseData(exception.cause?.response?.data);
+
+    final message =
+        _firstNonEmpty([payload.message, exception.message]) ??
+        '요청 처리 중 오류가 발생했습니다.';
+
+    final reasons = payload.reasons
+        .where(
+          (reason) =>
+              reason.trim().toLowerCase() != message.trim().toLowerCase(),
+        )
+        .toList(growable: false);
+
+    return Failure(
+      message: message,
+      code: exception.code,
+      statusCode: exception.statusCode,
+      reasons: reasons,
+      fieldErrors: payload.fieldErrors.map(
+        (key, value) => MapEntry(key, _dedupeStrings(value)),
+      ),
+      raw: exception,
+    );
+  }
+
+  String _exceptionMessage(Object error) {
+    final raw = error.toString();
+    final trimmed = raw.trim();
+    if (trimmed.startsWith('Exception: ')) {
+      final stripped = trimmed.substring('Exception: '.length).trim();
+      if (stripped.isNotEmpty) {
+        return stripped;
+      }
+    }
+    if (trimmed.startsWith('Error: ')) {
+      final stripped = trimmed.substring('Error: '.length).trim();
+      if (stripped.isNotEmpty) {
+        return stripped;
+      }
+    }
+    return trimmed.isEmpty ? '요청 처리 중 오류가 발생했습니다.' : trimmed;
+  }
+}
+
+class _FailurePayload {
+  String? message;
+  final List<String> reasons = [];
+  final Map<String, List<String>> fieldErrors = {};
+
+  void consumeDetails(Map<String, dynamic>? details) {
+    if (details == null || details.isEmpty) {
+      return;
+    }
+    details.forEach((rawKey, rawValue) {
+      final key = rawKey.toString();
+      final values = _flattenMessages(rawValue);
+      if (values.isEmpty) {
+        return;
+      }
+      if (_isGeneralKey(key)) {
+        reasons.addAll(values);
+      } else {
+        fieldErrors.putIfAbsent(key, () => <String>[]).addAll(values);
+      }
+    });
+  }
+
+  void consumeResponseData(dynamic data) {
+    if (data == null) {
+      return;
+    }
+    if (data is Map<String, dynamic>) {
+      _consumeMap(data);
+      return;
+    }
+    if (data is Iterable) {
+      reasons.addAll(_flattenIterable(data));
+      return;
+    }
+    final text = _toMessage(data);
+    if (text != null) {
+      reasons.add(text);
+    }
+  }
+
+  void _consumeMap(Map<String, dynamic> map) {
+    final messageCandidate = _firstNonEmpty([
+      _toMessage(map['message']),
+      _toMessage(map['error_message']),
+      _toMessage(map['errorMessage']),
+      _toMessage(map['detail']),
+    ]);
+    if (messageCandidate != null) {
+      message = messageCandidate;
+    }
+
+    _consumeErrorsNode(map['errors']);
+    _consumeErrorsNode(map['details']);
+    _consumeErrorsNode(map['reason']);
+    _consumeErrorsNode(map['reasons']);
+    _consumeErrorsNode(map['context']);
+
+    final errorNode = map['error'];
+    if (errorNode is Map<String, dynamic>) {
+      final nodeMessage = _firstNonEmpty([
+        _toMessage(errorNode['message']),
+        _toMessage(errorNode['title']),
+        _toMessage(errorNode['detail']),
+      ]);
+      message ??= nodeMessage;
+      _consumeErrorsNode(errorNode['errors']);
+      _consumeErrorsNode(errorNode['details']);
+      _consumeErrorsNode(errorNode['reason']);
+      _consumeErrorsNode(errorNode['reasons']);
+      _consumeErrorsNode(errorNode['context']);
+      final extra = _flattenIterable(_ensureIterable(errorNode['messages']));
+      reasons.addAll(extra);
+    } else if (errorNode != null) {
+      final text = _toMessage(errorNode);
+      if (text != null) {
+        reasons.add(text);
+      }
+    }
+
+    final messagesNode = map['messages'];
+    reasons.addAll(_flattenIterable(_ensureIterable(messagesNode)));
+  }
+
+  void _consumeErrorsNode(dynamic node) {
+    if (node == null) {
+      return;
+    }
+    if (node is Map<String, dynamic>) {
+      node.forEach((rawKey, rawValue) {
+        final key = rawKey.toString();
+        final values = _flattenMessages(rawValue);
+        if (values.isEmpty) {
+          return;
+        }
+        if (_isGeneralKey(key)) {
+          reasons.addAll(values);
+        } else {
+          fieldErrors.putIfAbsent(key, () => <String>[]).addAll(values);
+        }
+      });
+      return;
+    }
+    if (node is Iterable) {
+      for (final item in node) {
+        if (item is Map<String, dynamic>) {
+          final field = _firstNonEmpty([
+            _toMessage(item['field']),
+            _toMessage(item['name']),
+            _toMessage(item['key']),
+          ]);
+          final messages = _flattenMessages(
+            item['messages'] ??
+                item['message'] ??
+                item['detail'] ??
+                item['error'],
+          );
+          if (field != null && field.trim().isNotEmpty) {
+            if (messages.isEmpty) {
+              final fallback = _flattenMessages(item);
+              fieldErrors.putIfAbsent(field, () => <String>[]).addAll(fallback);
+            } else {
+              fieldErrors.putIfAbsent(field, () => <String>[]).addAll(messages);
+            }
+          } else if (messages.isNotEmpty) {
+            reasons.addAll(messages);
+          } else {
+            reasons.addAll(_flattenMessages(item.values));
+          }
+        } else {
+          reasons.addAll(_flattenMessages(item));
+        }
+      }
+      return;
+    }
+    final values = _flattenMessages(node);
+    if (values.isNotEmpty) {
+      reasons.addAll(values);
+    }
+  }
+}
+
+const Set<String> _generalErrorKeys = {
+  'general',
+  'base',
+  'common',
+  'global',
+  '_global',
+  '_common',
+  '_general',
+  'summary',
+  'message',
+  'messages',
+  'detail',
+  'details',
+  'reason',
+  'reasons',
+  'non_field_errors',
+  'nonfielderrors',
+};
+
+bool _isGeneralKey(String key) {
+  final normalized = key.trim().toLowerCase();
+  return _generalErrorKeys.contains(normalized);
+}
+
+Iterable<dynamic> _ensureIterable(dynamic value) {
+  if (value is Iterable) {
+    return value;
+  }
+  if (value == null) {
+    return const [];
+  }
+  return [value];
+}
+
+String? _firstNonEmpty(Iterable<String?> candidates) {
+  for (final candidate in candidates) {
+    final text = candidate?.trim();
+    if (text != null && text.isNotEmpty) {
+      return text;
+    }
+  }
+  return null;
+}
+
+String? _toMessage(dynamic value) {
+  if (value == null) {
+    return null;
+  }
+  if (value is String) {
+    final trimmed = value.trim();
+    return trimmed.isEmpty ? null : trimmed;
+  }
+  if (value is num || value is bool) {
+    return value.toString();
+  }
+  return null;
+}
+
+List<String> _flattenIterable(Iterable<dynamic> values) {
+  final aggregated = <String>[];
+  for (final value in values) {
+    aggregated.addAll(_flattenMessages(value));
+  }
+  return aggregated;
+}
+
+List<String> _flattenMessages(dynamic value) {
+  if (value == null) {
+    return const [];
+  }
+  if (value is String) {
+    final trimmed = value.trim();
+    return trimmed.isEmpty ? const [] : [trimmed];
+  }
+  if (value is num || value is bool) {
+    return [value.toString()];
+  }
+  if (value is Iterable) {
+    return _flattenIterable(value);
+  }
+  if (value is Map) {
+    final map = value.cast<dynamic, dynamic>();
+    final candidates = <String>[];
+    final directMessage = _firstNonEmpty([
+      _toMessage(map['message']),
+      _toMessage(map['detail']),
+      _toMessage(map['error']),
+      _toMessage(map['description']),
+      _toMessage(map['reason']),
+      _toMessage(map['title']),
+    ]);
+    if (directMessage != null) {
+      candidates.add(directMessage);
+    }
+    final messagesNode = map['messages'];
+    if (messagesNode is Iterable) {
+      candidates.addAll(_flattenIterable(messagesNode));
+    }
+    if (candidates.isNotEmpty) {
+      return candidates;
+    }
+    return _flattenIterable(map.values);
+  }
+  return [_toMessage(value) ?? value.toString()];
+}
+
+List<String> _dedupeStrings(Iterable<String> values) {
+  final result = <String>[];
+  final seen = <String>{};
+  for (final value in values) {
+    final trimmed = value.trim();
+    if (trimmed.isEmpty) {
+      continue;
+    }
+    final normalized = trimmed.toLowerCase();
+    if (seen.add(normalized)) {
+      result.add(trimmed);
+    }
+  }
+  return result;
+}
diff --git a/lib/core/permissions/permission_manager.dart b/lib/core/permissions/permission_manager.dart
index cb861b9..ead20b1 100644
--- a/lib/core/permissions/permission_manager.dart
+++ b/lib/core/permissions/permission_manager.dart
@@ -1,6 +1,7 @@
 import 'package:flutter/widgets.dart';
 
 import '../config/environment.dart';
+import 'permission_resources.dart';
 
 /// 권한 체크를 위한 액션 종류.
 enum PermissionAction { view, create, edit, delete, restore, approve }
@@ -9,16 +10,20 @@ enum PermissionAction { view, create, edit, delete, restore, approve }
 class PermissionManager extends ChangeNotifier {
   PermissionManager({Map<String, Set<PermissionAction>>? overrides}) {
     if (overrides != null) {
-      _overrides.addAll(overrides);
+      updateOverrides(overrides);
     }
   }
 
   /// 리소스별 임시 권한 집합을 보관한다.
   final Map<String, Set<PermissionAction>> _overrides = {};
 
+  /// 서버에서 내려받은 실제 권한 집합.
+  final Map<String, Set<PermissionAction>> _serverPermissions = {};
+
   /// 지정한 리소스/행동이 허용되는지 여부를 반환한다.
   bool can(String resource, PermissionAction action) {
-    final override = _overrides[resource];
+    final key = _normalize(resource);
+    final override = _overrides[key];
     if (override != null) {
       // View 권한은 최소 접근을 허용하기 위해 별도로 처리한다.
       if (override.contains(PermissionAction.view) &&
@@ -27,16 +32,50 @@ class PermissionManager extends ChangeNotifier {
       }
       return override.contains(action);
     }
-    return Environment.hasPermission(resource, action.name);
+
+    final server = _serverPermissions[key];
+    if (server != null) {
+      if (action == PermissionAction.view) {
+        return server.contains(PermissionAction.view);
+      }
+      return server.contains(action);
+    }
+
+    return Environment.hasPermission(key, action.name);
   }
 
   /// 개발/테스트 환경에서 사용할 임시 오버라이드 값을 설정한다.
   void updateOverrides(Map<String, Set<PermissionAction>> overrides) {
     _overrides
       ..clear()
-      ..addAll(overrides);
+      ..addAll(
+        overrides.map((key, value) => MapEntry(_normalize(key), value.toSet())),
+      );
     notifyListeners();
   }
+
+  /// 서버에서 내려온 권한 정보를 적용한다.
+  void applyServerPermissions(Map<String, Set<PermissionAction>> permissions) {
+    _serverPermissions
+      ..clear()
+      ..addAll(
+        permissions.map(
+          (key, value) => MapEntry(_normalize(key), value.toSet()),
+        ),
+      );
+    notifyListeners();
+  }
+
+  /// 서버 권한 정보를 초기화한다.
+  void clearServerPermissions() {
+    if (_serverPermissions.isEmpty) {
+      return;
+    }
+    _serverPermissions.clear();
+    notifyListeners();
+  }
+
+  String _normalize(String resource) => PermissionResources.normalize(resource);
 }
 
 /// 위젯 트리에 [PermissionManager]를 전달하는 Inherited 위젯.
diff --git a/test/core/network/api_error_test.dart b/test/core/network/api_error_test.dart
new file mode 100644
index 0000000..d7916de
--- /dev/null
+++ b/test/core/network/api_error_test.dart
@@ -0,0 +1,83 @@
+import 'package:dio/dio.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:superport_v2/core/network/api_error.dart';
+
+void main() {
+  group('ApiErrorMapper', () {
+    test('중첩 error 노드에서 메시지와 상세를 추출한다', () {
+      final mapper = ApiErrorMapper();
+      final requestOptions = RequestOptions(path: '/groups');
+      final dioException = DioException(
+        requestOptions: requestOptions,
+        type: DioExceptionType.badResponse,
+        response: Response<dynamic>(
+          requestOptions: requestOptions,
+          statusCode: 422,
+          data: {
+            'error': {
+              'message': '그룹 이름이 이미 존재합니다.',
+              'details': [
+                {'field': 'group_name', 'message': '중복된 그룹 이름입니다.'},
+              ],
+            },
+          },
+        ),
+      );
+
+      final exception = mapper.map(dioException);
+
+      expect(exception.message, '그룹 이름이 이미 존재합니다.');
+      expect(exception.statusCode, 422);
+      expect(exception.details, isNotNull);
+      final details = exception.details!['group_name'];
+      if (details is Iterable) {
+        expect(details, contains('중복된 그룹 이름입니다.'));
+      } else {
+        expect(details, '중복된 그룹 이름입니다.');
+      }
+    });
+  });
+
+  test('403 권한 오류 응답에서 세부 정보를 유지한다', () {
+    final mapper = ApiErrorMapper();
+    final requestOptions = RequestOptions(path: '/stock-transactions/1');
+    final dioException = DioException(
+      requestOptions: requestOptions,
+      type: DioExceptionType.badResponse,
+      response: Response<dynamic>(
+        requestOptions: requestOptions,
+        statusCode: 403,
+        data: {
+          'error': {
+            'code': 'permission_denied',
+            'message': '승인 권한이 없습니다.',
+            'details': {'action': 'approve'},
+            'context': {'resource': 'stock-transactions'},
+          },
+        },
+      ),
+    );
+
+    final exception = mapper.map(dioException);
+
+    expect(exception.code, ApiErrorCode.forbidden);
+    expect(exception.message, '승인 권한이 없습니다.');
+    final details = exception.details!;
+    final action = details['action'];
+    final resource = details['resource'];
+
+    Iterable<dynamic> asIterable(dynamic value) {
+      if (value == null) {
+        return const [];
+      }
+      if (value is Iterable) {
+        return value;
+      }
+      return [value];
+    }
+
+    expect(asIterable(action), contains('approve'));
+    expect(asIterable(resource), contains('stock-transactions'));
+  });
+}
diff --git a/test/core/network/failure_parser_test.dart b/test/core/network/failure_parser_test.dart
new file mode 100644
index 0000000..471ee13
--- /dev/null
+++ b/test/core/network/failure_parser_test.dart
@@ -0,0 +1,107 @@
+import 'package:dio/dio.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:superport_v2/core/network/api_error.dart';
+import 'package:superport_v2/core/network/failure.dart';
+
+void main() {
+  group('FailureParser', () {
+    test('ApiException에서 메시지·필드 오류를 추출한다', () {
+      final requestOptions = RequestOptions(path: '/test');
+      final dioException = DioException(
+        requestOptions: requestOptions,
+        type: DioExceptionType.badResponse,
+        response: Response<dynamic>(
+          requestOptions: requestOptions,
+          statusCode: 422,
+          data: {
+            'error': {
+              'message': '입력값을 확인해 주세요.',
+              'details': [
+                {'field': 'quantity', 'message': '수량은 1 이상 입력해야 합니다.'},
+                {'field': 'general', 'message': '재고 상태가 출고 불가 상태입니다.'},
+              ],
+            },
+          },
+        ),
+      );
+
+      final exception = ApiException(
+        code: ApiErrorCode.unprocessableEntity,
+        message: '요청 처리 중 오류가 발생했습니다.',
+        statusCode: 422,
+        cause: dioException,
+      );
+
+      final failure = Failure.from(exception);
+
+      expect(failure.message, '입력값을 확인해 주세요.');
+      expect(failure.fieldErrors['quantity'], isNotNull);
+      expect(failure.fieldErrors['quantity'], contains('수량은 1 이상 입력해야 합니다.'));
+      final description = failure.describe();
+      expect(description, contains('입력값을 확인해 주세요.'));
+      expect(description, contains('quantity: 수량은 1 이상 입력해야 합니다.'));
+      expect(description, contains('재고 상태가 출고 불가 상태입니다.'));
+    });
+
+    test('일반 Exception은 접두사를 제거한 메시지를 반환한다', () {
+      final exception = Exception('네트워크 오류');
+
+      final failure = Failure.from(exception);
+
+      expect(failure.message, '네트워크 오류');
+      expect(failure.describe(), '네트워크 오류');
+    });
+
+    test('필드 오류만 존재해도 describe에 요약이 포함된다', () {
+      final exception = ApiException(
+        code: ApiErrorCode.badRequest,
+        message: '잘못된 요청입니다.',
+        details: {
+          'approval_id': ['결재 ID를 입력하세요.'],
+          'step_order': ['단계 순서를 입력하세요.'],
+        },
+      );
+
+      final failure = Failure.from(exception);
+
+      expect(failure.fieldErrors.keys, contains('approval_id'));
+      final summary = failure.describe();
+      expect(summary, contains('approval_id: 결재 ID를 입력하세요.'));
+      expect(summary, contains('step_order: 단계 순서를 입력하세요.'));
+    });
+  });
+
+  test('권한 오류에서 코드·메시지·세부 정보를 추출한다', () {
+    final requestOptions = RequestOptions(
+      path: '/stock-transactions/42/approve',
+    );
+    final dioException = DioException(
+      requestOptions: requestOptions,
+      type: DioExceptionType.badResponse,
+      response: Response<dynamic>(
+        requestOptions: requestOptions,
+        statusCode: 403,
+        data: {
+          'error': {
+            'code': 'permission_denied',
+            'message': '승인 권한이 없습니다.',
+            'reasons': ['결재 관리자만 승인할 수 있습니다.'],
+            'context': {'resource': 'stock-transactions', 'action': 'approve'},
+          },
+        },
+      ),
+    );
+
+    final failure = Failure.from(dioException);
+
+    expect(failure.code, ApiErrorCode.forbidden);
+    expect(failure.message, '승인 권한이 없습니다.');
+    expect(failure.reasons, contains('결재 관리자만 승인할 수 있습니다.'));
+    expect(failure.fieldErrors['action'], isNotNull);
+    expect(failure.fieldErrors['action'], contains('approve'));
+    final description = failure.describe();
+    expect(description, contains('승인 권한이 없습니다.'));
+    expect(description, contains('action: approve'));
+  });
+}
diff --git a/test/core/permissions/permission_manager_test.dart b/test/core/permissions/permission_manager_test.dart
index b6029ce..88cdbd1 100644
--- a/test/core/permissions/permission_manager_test.dart
+++ b/test/core/permissions/permission_manager_test.dart
@@ -1,73 +1,96 @@
-import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
+
 import 'package:superport_v2/core/permissions/permission_manager.dart';
+import 'package:superport_v2/core/permissions/permission_resources.dart';
 
 void main() {
   group('PermissionManager', () {
-    test('falls back to environment permissions when no override', () {
+    test('서버 권한을 적용하면 해당 리소스 권한이 설정된다', () {
       final manager = PermissionManager();
-      final allowed = manager.can('/any', PermissionAction.view);
-      expect(allowed, isTrue);
-    });
 
-    test('respects overrides', () {
-      final manager = PermissionManager(
-        overrides: {
-          '/inventory/inbound': {
-            PermissionAction.view,
-            PermissionAction.create,
-          },
+      manager.applyServerPermissions({
+        PermissionResources.stockTransactions: {
+          PermissionAction.view,
+          PermissionAction.create,
         },
-      );
-      expect(manager.can('/inventory/inbound', PermissionAction.view), isTrue);
+      });
+
       expect(
-        manager.can('/inventory/inbound', PermissionAction.create),
+        manager.can(
+          PermissionResources.stockTransactions,
+          PermissionAction.view,
+        ),
         isTrue,
       );
       expect(
-        manager.can('/inventory/inbound', PermissionAction.delete),
+        manager.can(
+          PermissionResources.stockTransactions,
+          PermissionAction.create,
+        ),
+        isTrue,
+      );
+      expect(
+        manager.can(
+          PermissionResources.stockTransactions,
+          PermissionAction.edit,
+        ),
+        isFalse,
+      );
+    });
+
+    test('오버라이드가 서버 권한보다 우선한다', () {
+      final manager = PermissionManager();
+
+      manager.applyServerPermissions({
+        PermissionResources.approvalSteps: {PermissionAction.view},
+      });
+      manager.updateOverrides({
+        PermissionResources.approvalSteps: {PermissionAction.edit},
+      });
+
+      expect(
+        manager.can(PermissionResources.approvalSteps, PermissionAction.edit),
+        isTrue,
+      );
+      expect(
+        manager.can(PermissionResources.approvalSteps, PermissionAction.view),
+        isFalse,
+      );
+    });
+
+    test('서버 권한을 초기화하면 환경 설정으로 되돌아간다', () {
+      final manager = PermissionManager();
+      manager.applyServerPermissions({
+        PermissionResources.vendors: {PermissionAction.view},
+      });
+      expect(
+        manager.can(PermissionResources.vendors, PermissionAction.edit),
+        isFalse,
+      );
+
+      manager.clearServerPermissions();
+
+      // 환경 설정에 권한이 명시되지 않으면 기본적으로 허용한다.
+      expect(
+        manager.can(PermissionResources.vendors, PermissionAction.edit),
+        isTrue,
+      );
+    });
+
+    test('별칭 경로도 normalize되어 권한을 확인한다', () {
+      final manager = PermissionManager();
+      manager.applyServerPermissions({
+        PermissionResources.stockTransactions: {PermissionAction.view},
+      });
+
+      expect(
+        manager.can('/Inventory/Inbound?page=1', PermissionAction.view),
+        isTrue,
+      );
+      expect(
+        manager.can('/inventory/outbound', PermissionAction.edit),
         isFalse,
       );
     });
   });
-
-  testWidgets('PermissionGate hides child when unauthorized', (tester) async {
-    final manager = PermissionManager(overrides: {'/resource': {}});
-    await tester.pumpWidget(
-      PermissionScope(
-        manager: manager,
-        child: const Directionality(
-          textDirection: TextDirection.ltr,
-          child: PermissionGate(
-            resource: '/resource',
-            action: PermissionAction.view,
-            child: Text('secret'),
-          ),
-        ),
-      ),
-    );
-
-    expect(find.text('secret'), findsNothing);
-  });
-
-  testWidgets('PermissionGate shows fallback when provided', (tester) async {
-    final manager = PermissionManager(overrides: {'/resource': {}});
-    await tester.pumpWidget(
-      PermissionScope(
-        manager: manager,
-        child: const Directionality(
-          textDirection: TextDirection.ltr,
-          child: PermissionGate(
-            resource: '/resource',
-            action: PermissionAction.view,
-            fallback: Text('fallback'),
-            child: Text('secret'),
-          ),
-        ),
-      ),
-    );
-
-    expect(find.text('fallback'), findsOneWidget);
-    expect(find.text('secret'), findsNothing);
-  });
 }
diff --git a/test/core/permissions/permission_resources_test.dart b/test/core/permissions/permission_resources_test.dart
new file mode 100644
index 0000000..c0502f0
--- /dev/null
+++ b/test/core/permissions/permission_resources_test.dart
@@ -0,0 +1,48 @@
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:superport_v2/core/permissions/permission_resources.dart';
+
+void main() {
+  group('PermissionResources.normalize', () {
+    test('경로 별칭을 서버 표준 경로로 변환한다', () {
+      expect(
+        PermissionResources.normalize('/inventory/inbound'),
+        PermissionResources.stockTransactions,
+      );
+      expect(
+        PermissionResources.normalize('/approvals/templates'),
+        PermissionResources.approvalTemplates,
+      );
+    });
+
+    test('대소문자/공백/슬래시를 정리한다', () {
+      expect(
+        PermissionResources.normalize('  inventory/inbound/  '),
+        PermissionResources.stockTransactions,
+      );
+      expect(
+        PermissionResources.normalize('stock-transactions'),
+        PermissionResources.stockTransactions,
+      );
+    });
+
+    test('쿼리/프래그먼트/URL을 제거한다', () {
+      expect(
+        PermissionResources.normalize(
+          '/Inventory/Inbound?page=2&status=submit',
+        ),
+        PermissionResources.stockTransactions,
+      );
+      expect(
+        PermissionResources.normalize(
+          'https://example.com/approvals/templates#section',
+        ),
+        PermissionResources.approvalTemplates,
+      );
+    });
+
+    test('비어 있는 입력은 빈 문자열을 반환한다', () {
+      expect(PermissionResources.normalize('   '), isEmpty);
+    });
+  });
+}