diff --git a/.env.example b/.env.example
index 8bc28d1..17693c1 100644
--- a/.env.example
+++ b/.env.example
@@ -10,8 +10,8 @@ PURCHASE_TELEPAGOS_EXPIRATION_MINUTES=30
 PURCHASE_TRANSFER_EXPIRATION_MINUTES=1440
 FRONTEND_URLS=http://localhost:4200
 
-APP_LOCALE=en
-APP_FALLBACK_LOCALE=en
+APP_LOCALE=es
+APP_FALLBACK_LOCALE=es
 APP_FAKER_LOCALE=en_US
 
 APP_MAINTENANCE_DRIVER=file
diff --git a/app/Domains/Auth/Controllers/CreateResetPasswordAttemptController.php b/app/Domains/Auth/Controllers/CreateResetPasswordAttemptController.php
index 919cf3c..cc52307 100644
--- a/app/Domains/Auth/Controllers/CreateResetPasswordAttemptController.php
+++ b/app/Domains/Auth/Controllers/CreateResetPasswordAttemptController.php
@@ -24,7 +24,8 @@ class CreateResetPasswordAttemptController extends Controller
         );
 
         return response()->json([
-            'message' => 'Si el email está registrado, recibirás un código para recuperar tu contraseña.',
+            'code' => 'auth.password_reset_requested',
+            'message' => __('api.auth.password_reset_requested'),
             'status' => ResetPasswordAttempt::STATUS_PENDING,
         ], 202);
     }
diff --git a/app/Domains/Auth/Controllers/GoogleTokenExchangeController.php b/app/Domains/Auth/Controllers/GoogleTokenExchangeController.php
index 63c4250..1aaa181 100644
--- a/app/Domains/Auth/Controllers/GoogleTokenExchangeController.php
+++ b/app/Domains/Auth/Controllers/GoogleTokenExchangeController.php
@@ -35,7 +35,8 @@ class GoogleTokenExchangeController extends Controller
         );
 
         $response = response()->json([
-            'message' => 'Sesion iniciada correctamente.',
+            'code' => 'auth.login_success',
+            'message' => __('api.auth.login_success'),
             'token' => $authentication['token'],
             'token_type' => 'Bearer',
             'user' => UserResource::make($authentication['user']),
diff --git a/app/Domains/Auth/Controllers/LoginController.php b/app/Domains/Auth/Controllers/LoginController.php
index 00ad8f7..bfdab97 100644
--- a/app/Domains/Auth/Controllers/LoginController.php
+++ b/app/Domains/Auth/Controllers/LoginController.php
@@ -28,7 +28,7 @@ class LoginController extends Controller
 
         if (! $user || ! Hash::check($credentials['password'], $user->password)) {
             throw ValidationException::withMessages([
-                'email' => 'Email o Contraseña incorrectos.',
+                'email' => __('api.auth.invalid_credentials'),
             ]);
         }
 
@@ -50,7 +50,8 @@ class LoginController extends Controller
         );
 
         $response = response()->json([
-            'message' => 'Sesion iniciada correctamente.',
+            'code' => 'auth.login_success',
+            'message' => __('api.auth.login_success'),
             'token' => $token,
             'token_type' => 'Bearer',
             'user' => UserResource::make($user),
diff --git a/app/Domains/Auth/Controllers/LogoutController.php b/app/Domains/Auth/Controllers/LogoutController.php
index 3b4499f..c6b1f78 100644
--- a/app/Domains/Auth/Controllers/LogoutController.php
+++ b/app/Domains/Auth/Controllers/LogoutController.php
@@ -23,7 +23,8 @@ class LogoutController extends Controller
         }
 
         return response()->json([
-            'message' => 'Sesion cerrada correctamente.',
+            'code' => 'auth.logout_success',
+            'message' => __('api.auth.logout_success'),
         ]);
     }
 }
diff --git a/app/Domains/Auth/Controllers/RegisterController.php b/app/Domains/Auth/Controllers/RegisterController.php
index 98ec675..95dbe29 100644
--- a/app/Domains/Auth/Controllers/RegisterController.php
+++ b/app/Domains/Auth/Controllers/RegisterController.php
@@ -12,15 +12,17 @@ class RegisterController extends Controller
 {
     public function __construct(
         protected RegisterUserService $registerUserService,
-    ) {
-    }
+    ) {}
 
     public function __invoke(RegisterUserRequest $request): JsonResponse
     {
         $user = $this->registerUserService->register($request->validated());
 
         return UserResource::make($user)
-            ->additional(['message' => 'Usuario registrado correctamente.'])
+            ->additional([
+                'code' => 'auth.register_success',
+                'message' => __('api.auth.register_success'),
+            ])
             ->response()
             ->setStatusCode(201);
     }
diff --git a/app/Domains/Auth/Controllers/ResetPasswordController.php b/app/Domains/Auth/Controllers/ResetPasswordController.php
index a355a1d..5411a97 100644
--- a/app/Domains/Auth/Controllers/ResetPasswordController.php
+++ b/app/Domains/Auth/Controllers/ResetPasswordController.php
@@ -28,12 +28,13 @@ class ResetPasswordController extends Controller
             $data['password'],
         )) {
             throw ValidationException::withMessages([
-                'codigo' => 'La solicitud de recuperación es inválida o ya fue utilizada.',
+                'codigo' => __('api.auth.password_reset_invalid'),
             ]);
         }
 
         return response()->json([
-            'message' => 'Contraseña modificada correctamente.',
+            'code' => 'auth.password_updated',
+            'message' => __('api.auth.password_updated'),
             'status' => ResetPasswordAttempt::STATUS_USED,
         ]);
     }
diff --git a/app/Domains/Auth/Controllers/ValidateResetPasswordAttemptController.php b/app/Domains/Auth/Controllers/ValidateResetPasswordAttemptController.php
index 7905602..07fc705 100644
--- a/app/Domains/Auth/Controllers/ValidateResetPasswordAttemptController.php
+++ b/app/Domains/Auth/Controllers/ValidateResetPasswordAttemptController.php
@@ -27,12 +27,13 @@ class ValidateResetPasswordAttemptController extends Controller
             $data['codigo'],
         )) {
             throw ValidationException::withMessages([
-                'codigo' => 'El código ingresado es inválido.',
+                'codigo' => __('api.auth.reset_code_invalid'),
             ]);
         }
 
         return response()->json([
-            'message' => 'Código validado correctamente.',
+            'code' => 'auth.reset_code_valid',
+            'message' => __('api.auth.reset_code_valid'),
             'status' => ResetPasswordAttempt::STATUS_VALIDATED,
         ]);
     }
diff --git a/app/Domains/Auth/Services/GoogleAuthService.php b/app/Domains/Auth/Services/GoogleAuthService.php
index d90d774..364c09f 100644
--- a/app/Domains/Auth/Services/GoogleAuthService.php
+++ b/app/Domains/Auth/Services/GoogleAuthService.php
@@ -25,7 +25,7 @@ class GoogleAuthService
 
         if (! $tenant || ! $this->isTenantReturnUrl($returnUrl, $tenant)) {
             throw ValidationException::withMessages([
-                'tenant' => 'El tenant o la URL de retorno no son validos.',
+                'tenant' => __('api.auth.invalid_tenant_or_return_url'),
             ]);
         }
 
@@ -50,13 +50,13 @@ class GoogleAuthService
         $context = Str::isUuid($state) ? Cache::pull("google-oauth-context:{$state}") : null;
 
         if (! is_array($context) || ! isset($context['tenant_codigo'], $context['return_url'])) {
-            abort(400, 'La solicitud de autenticacion expiro. Intenta nuevamente.');
+            abort(400, __('api.auth.request_expired'));
         }
 
         $tenant = Tenant::query()->where('codigo', $context['tenant_codigo'])->first();
 
         if (! $tenant || ! $this->isTenantReturnUrl($context['return_url'], $tenant)) {
-            abort(400, 'La URL de retorno no es valida.');
+            abort(400, __('api.auth.invalid_return_url'));
         }
 
         /** @var SocialiteUser $googleUser */
@@ -88,13 +88,13 @@ class GoogleAuthService
 
         if (! $authentication) {
             throw ValidationException::withMessages([
-                'oauth_code' => 'El codigo de autenticacion expiro o ya fue utilizado.',
+                'oauth_code' => __('api.auth.oauth_code_expired'),
             ]);
         }
 
         if (($authentication['tenant_codigo'] ?? null) !== $tenantCodigo) {
             throw ValidationException::withMessages([
-                'tenant_codigo' => 'El tenant no coincide con la solicitud de autenticacion.',
+                'tenant_codigo' => __('api.auth.tenant_mismatch'),
             ]);
         }
 
@@ -112,7 +112,7 @@ class GoogleAuthService
 
         if (! is_string($googleId) || $googleId === '' || ! is_string($email) || ! filter_var($email, FILTER_VALIDATE_EMAIL)) {
             throw ValidationException::withMessages([
-                'google' => 'Google no devolvio una identidad valida.',
+                'google' => __('api.auth.google_email_required'),
             ]);
         }
 
@@ -120,7 +120,7 @@ class GoogleAuthService
         $emailVerified = $rawUser['email_verified'] ?? $rawUser['verified_email'] ?? false;
         if (! in_array($emailVerified, [true, 'true', 1, '1'], true)) {
             throw ValidationException::withMessages([
-                'google' => 'La cuenta de Google debe tener el email verificado.',
+                'google' => __('api.auth.google_email_unverified'),
             ]);
         }
 
diff --git a/app/Domains/Cart/Controllers/CartController.php b/app/Domains/Cart/Controllers/CartController.php
index bde6581..88524ba 100644
--- a/app/Domains/Cart/Controllers/CartController.php
+++ b/app/Domains/Cart/Controllers/CartController.php
@@ -36,7 +36,10 @@ class CartController extends Controller
         );
 
         $response = CartResource::make($result['cart'])
-            ->additional(['message' => 'Producto agregado al carrito.'])
+            ->additional([
+                'code' => 'cart.item_added',
+                'message' => __('api.cart.item_added'),
+            ])
             ->response();
 
         if ($result['guest_token'] !== null) {
@@ -58,13 +61,19 @@ class CartController extends Controller
                 $cartItem->getKey(),
                 (int) $request->validated('cantidad'),
             )
-        )->additional(['message' => 'Cantidad de producto actualizada.']);
+        )->additional([
+            'code' => 'cart.quantity_updated',
+            'message' => __('api.cart.quantity_updated'),
+        ]);
     }
 
     public function removeItem(Request $request, Tenant $tenant, CartItem $cartItem): CartResource
     {
         return CartResource::make(
             $this->cartService->removeItem($tenant, $request, $cartItem->getKey())
-        )->additional(['message' => 'Producto eliminado del carrito.']);
+        )->additional([
+            'code' => 'cart.item_removed',
+            'message' => __('api.cart.item_removed'),
+        ]);
     }
 }
diff --git a/app/Domains/Cart/Models/Cart.php b/app/Domains/Cart/Models/Cart.php
index 20ff68d..f4f1aca 100644
--- a/app/Domains/Cart/Models/Cart.php
+++ b/app/Domains/Cart/Models/Cart.php
@@ -79,7 +79,7 @@ class Cart extends Model
     {
         if ($quantity <= 0) {
             throw ValidationException::withMessages([
-                'cantidad' => 'La cantidad debe ser mayor a cero.',
+                'cantidad' => __('api.cart.positive_quantity'),
             ]);
         }
 
@@ -91,7 +91,7 @@ class Cart extends Model
 
             if ($availableQuantity !== null && $availableQuantity < $quantity) {
                 throw ValidationException::withMessages([
-                    'cantidad' => "Stock insuficiente para el producto solicitado. Maximo disponible: {$availableQuantity}.",
+                    'cantidad' => __('api.cart.insufficient_stock', ['max' => $availableQuantity]),
                 ]);
             }
 
@@ -123,7 +123,7 @@ class Cart extends Model
     {
         if ($quantity <= 0) {
             throw ValidationException::withMessages([
-                'cantidad' => 'La cantidad debe ser mayor a cero.',
+                'cantidad' => __('api.cart.positive_quantity'),
             ]);
         }
 
@@ -146,7 +146,7 @@ class Cart extends Model
             if ($delta > 0 && $availableQuantity !== null && $availableQuantity < $delta) {
                 $maxAvailable = $availableQuantity + $item->cantidad;
                 throw ValidationException::withMessages([
-                    'cantidad' => "El máximo que se puede agregar es {$maxAvailable}.",
+                    'cantidad' => __('api.cart.max_quantity', ['max' => $maxAvailable]),
                 ]);
             }
 
@@ -209,13 +209,13 @@ class Cart extends Model
         if ($catalogItem->isBundle()) {
             if ($variantId !== null) {
                 throw ValidationException::withMessages([
-                    'variant_id' => 'Un bundle no admite una variante.',
+                    'variant_id' => __('api.cart.bundle_variant_forbidden'),
                 ]);
             }
 
             if (! $catalogItem->bundleComponents()->exists()) {
                 throw ValidationException::withMessages([
-                    'catalog_item_id' => 'El bundle no tiene componentes.',
+                    'catalog_item_id' => __('api.cart.empty_bundle'),
                 ]);
             }
 
@@ -225,7 +225,7 @@ class Cart extends Model
         if ($variantId === null) {
             if ($catalogItem->inventory_id === null) {
                 throw ValidationException::withMessages([
-                    'variant_id' => 'Debe seleccionar una variante para este ítem.',
+                    'variant_id' => __('api.cart.variant_required'),
                 ]);
             }
 
diff --git a/app/Domains/Catalog/Services/CatalogService.php b/app/Domains/Catalog/Services/CatalogService.php
index e7a592a..0736f03 100644
--- a/app/Domains/Catalog/Services/CatalogService.php
+++ b/app/Domains/Catalog/Services/CatalogService.php
@@ -45,7 +45,7 @@ class CatalogService
             } else {
                 if (array_key_exists('components', $data)) {
                     throw ValidationException::withMessages([
-                        'components' => ['Un item standard no puede tener componentes.'],
+                        'components' => [__('api.catalog.standard_with_components')],
                     ]);
                 }
 
@@ -265,7 +265,7 @@ class CatalogService
 
             if (isset($seen[$key])) {
                 throw ValidationException::withMessages([
-                    "components.{$index}" => ['El componente esta duplicado.'],
+                    "components.{$index}" => [__('api.catalog.duplicate_component')],
                 ]);
             }
             $seen[$key] = true;
@@ -278,7 +278,7 @@ class CatalogService
             if ($componentItem === null) {
                 throw ValidationException::withMessages([
                     "components.{$index}.catalog_item_id" => [
-                        'El item no pertenece al tenant del bundle.',
+                        __('api.catalog.component_wrong_tenant'),
                     ],
                 ]);
             }
@@ -286,7 +286,7 @@ class CatalogService
             if ($componentItem->is($bundle) || $componentItem->type !== CatalogItemType::Standard) {
                 throw ValidationException::withMessages([
                     "components.{$index}.catalog_item_id" => [
-                        'El componente debe ser un item standard distinto del bundle.',
+                        __('api.catalog.invalid_component'),
                     ],
                 ]);
             }
@@ -295,7 +295,7 @@ class CatalogService
             if ($hasVariants && $variantId === null) {
                 throw ValidationException::withMessages([
                     "components.{$index}.variant_id" => [
-                        'Debe seleccionar una variante para este componente.',
+                        __('api.catalog.component_variant_required'),
                     ],
                 ]);
             }
@@ -303,7 +303,7 @@ class CatalogService
             if (! $hasVariants && $variantId !== null) {
                 throw ValidationException::withMessages([
                     "components.{$index}.variant_id" => [
-                        'El componente con inventario directo no admite una variante.',
+                        __('api.catalog.component_variant_forbidden'),
                     ],
                 ]);
             }
@@ -311,7 +311,7 @@ class CatalogService
             if ($variantId !== null && ! $componentItem->variants()->whereKey($variantId)->exists()) {
                 throw ValidationException::withMessages([
                     "components.{$index}.variant_id" => [
-                        'La variante no pertenece al componente indicado.',
+                        __('api.catalog.component_variant_invalid'),
                     ],
                 ]);
             }
@@ -333,7 +333,7 @@ class CatalogService
     {
         if ($components === []) {
             throw ValidationException::withMessages([
-                'components' => ['Un bundle debe tener al menos un componente.'],
+                'components' => [__('api.catalog.bundle_component_required')],
             ]);
         }
 
@@ -348,7 +348,7 @@ class CatalogService
         ] as $field) {
             if (array_key_exists($field, $data)) {
                 throw ValidationException::withMessages([
-                    $field => ["{$field} no se admite para un bundle."],
+                    $field => [__('api.catalog.bundle_field_forbidden', ['field' => $field])],
                 ]);
             }
         }
@@ -376,7 +376,7 @@ class CatalogService
 
             if ($attachment === null) {
                 throw ValidationException::withMessages([
-                    $validationKey => ['El attachment indicado no existe.'],
+                    $validationKey => [__('api.catalog.attachment_not_found')],
                 ]);
             }
 
@@ -408,7 +408,7 @@ class CatalogService
             if ($attribute === null) {
                 throw ValidationException::withMessages([
                     'attribute_codes' => [
-                        "El atributo {$attributeCode} no existe para el tenant del ítem.",
+                        __('api.catalog.attribute_not_found', ['attribute' => $attributeCode]),
                     ],
                 ]);
             }
@@ -442,7 +442,7 @@ class CatalogService
         ) {
             throw ValidationException::withMessages([
                 "variants.{$index}.inventory" => [
-                    'inventory_id, reserved_stock y sold_units son administrados internamente.',
+                    __('api.catalog.managed_inventory_fields'),
                 ],
             ]);
         }
@@ -463,7 +463,7 @@ class CatalogService
             if ($itemAttribute === null) {
                 throw ValidationException::withMessages([
                     "variants.{$index}.values.{$attributeCode}" => [
-                        'El atributo no pertenece al ítem de catálogo.',
+                        __('api.catalog.attribute_not_on_item'),
                     ],
                 ]);
             }
@@ -489,7 +489,7 @@ class CatalogService
         ) {
             throw ValidationException::withMessages([
                 "variants.{$index}.maximum_use_date" => [
-                    'La fecha maxima efectiva debe ser posterior o igual a la fecha minima efectiva.',
+                    __('api.catalog.invalid_effective_date_range'),
                 ],
             ]);
         }
@@ -508,7 +508,7 @@ class CatalogService
         if ($hasVariants && $variants === []) {
             throw ValidationException::withMessages([
                 'variants' => [
-                    'Un ítem con attribute_codes debe tener variantes.',
+                    __('api.catalog.variants_required'),
                 ],
             ]);
         }
@@ -516,7 +516,7 @@ class CatalogService
         if (! $hasVariants && $variants !== []) {
             throw ValidationException::withMessages([
                 'variants' => [
-                    'Un ítem sin attribute_codes no puede tener variantes.',
+                    __('api.catalog.variants_forbidden'),
                 ],
             ]);
         }
@@ -524,7 +524,7 @@ class CatalogService
         if ($hasVariants && $hasDirectStock) {
             throw ValidationException::withMessages([
                 'real_stock' => [
-                    'Un ítem con variantes no puede tener inventario directo.',
+                    __('api.catalog.direct_inventory_forbidden'),
                 ],
             ]);
         }
@@ -536,7 +536,7 @@ class CatalogService
         ) {
             throw ValidationException::withMessages([
                 'inventory' => [
-                    'inventory_id, reserved_stock y sold_units son administrados internamente.',
+                    __('api.catalog.managed_inventory_fields'),
                 ],
             ]);
         }
diff --git a/app/Domains/Integration/Controllers/TelepagosWebhookController.php b/app/Domains/Integration/Controllers/TelepagosWebhookController.php
index cdb6347..47c3a5b 100644
--- a/app/Domains/Integration/Controllers/TelepagosWebhookController.php
+++ b/app/Domains/Integration/Controllers/TelepagosWebhookController.php
@@ -6,28 +6,26 @@ use App\Domains\Integration\Requests\TelepagosWebhookRequest;
 use App\Domains\Integration\Services\TelepagosWebhookService;
 use App\Http\Controllers\Controller;
 use Illuminate\Http\JsonResponse;
-use Illuminate\Http\Request;
 
 class TelepagosWebhookController extends Controller
 {
     /**
      * Handle the incoming Telepagos webhook.
-     *
-     * @param TelepagosWebhookRequest $request
-     * @param string $tenantCodigo
-     * @param TelepagosWebhookService $service
-     * @return JsonResponse
      */
     public function handle(TelepagosWebhookRequest $request, string $tenantCodigo, TelepagosWebhookService $service): JsonResponse
     {
         try {
             $cashinId = $request->validated('id');
-            
+
             $service->handleWebhook($tenantCodigo, $cashinId);
-            
+
             return response()->json(['status' => 'success']);
         } catch (\Exception $e) {
-            return response()->json(['status' => 'error', 'message' => $e->getMessage()], 500);
+            return response()->json([
+                'status' => 'error',
+                'code' => 'integration.webhook_failed',
+                'message' => __('api.integration.webhook_failed'),
+            ], 500);
         }
     }
 }
diff --git a/app/Domains/Integration/Controllers/TenantIntegrationController.php b/app/Domains/Integration/Controllers/TenantIntegrationController.php
index 60b324c..b89f1b8 100644
--- a/app/Domains/Integration/Controllers/TenantIntegrationController.php
+++ b/app/Domains/Integration/Controllers/TenantIntegrationController.php
@@ -24,9 +24,12 @@ class TenantIntegrationController extends Controller
     public function show(string $tenantCode, string $integrationCode)
     {
         $integration = $this->tenantIntegrationService->getTenantIntegration($tenantCode, $integrationCode);
-        
-        if (!$integration) {
-            return response()->json(['message' => 'Integration not configured for this tenant'], 404);
+
+        if (! $integration) {
+            return response()->json([
+                'code' => 'integration.not_configured',
+                'message' => __('api.integration.not_configured'),
+            ], 404);
         }
 
         return response()->json($integration);
@@ -35,7 +38,7 @@ class TenantIntegrationController extends Controller
     public function store(StoreTenantIntegrationRequest $request, string $tenantCode, string $integrationCode)
     {
         $integration = Integration::where('integration_code', $integrationCode)->firstOrFail();
-        
+
         try {
             $this->tenantIntegrationService->updateOrCreateIntegration(
                 $tenantCode,
@@ -44,11 +47,13 @@ class TenantIntegrationController extends Controller
             );
 
             return response()->json([
-                'message' => 'integration configured correctly',
+                'code' => 'integration.configured',
+                'message' => __('api.integration.configured'),
             ]);
         } catch (\Exception $e) {
             return response()->json([
-                'message' => 'Error validando la configuración: ' . $e->getMessage()
+                'code' => 'integration.validation_failed',
+                'message' => __('api.integration.validation_failed', ['error' => $e->getMessage()]),
             ], 400);
         }
     }
diff --git a/app/Domains/Integration/Requests/StoreTenantIntegrationRequest.php b/app/Domains/Integration/Requests/StoreTenantIntegrationRequest.php
index d6d4d54..ddddd02 100644
--- a/app/Domains/Integration/Requests/StoreTenantIntegrationRequest.php
+++ b/app/Domains/Integration/Requests/StoreTenantIntegrationRequest.php
@@ -20,9 +20,9 @@ class StoreTenantIntegrationRequest extends FormRequest
         $integrationCode = $this->route('integration_code');
         $this->integrationModel = Integration::where('integration_code', $integrationCode)->first();
 
-        if (!$this->integrationModel) {
+        if (! $this->integrationModel) {
             throw ValidationException::withMessages([
-                'integration_code' => 'Integration not found.'
+                'integration_code' => __('api.integration.not_configured'),
             ]);
         }
     }
@@ -34,7 +34,7 @@ class StoreTenantIntegrationRequest extends FormRequest
         // Dynamic validation rules based on the integration data schema
         if ($this->integrationModel && $this->integrationModel->integration_data_schema) {
             foreach ($this->integrationModel->integration_data_schema as $field => $rule) {
-                $rules['integration_data.' . $field] = $rule;
+                $rules['integration_data.'.$field] = $rule;
             }
         }
 
diff --git a/app/Domains/MailTest/Services/MailTestService.php b/app/Domains/MailTest/Services/MailTestService.php
index 958e2ce..92c269b 100644
--- a/app/Domains/MailTest/Services/MailTestService.php
+++ b/app/Domains/MailTest/Services/MailTestService.php
@@ -24,7 +24,8 @@ class MailTestService
         );
 
         return [
-            'message' => 'Correo de prueba enviado correctamente.',
+            'code' => 'mail.test_sent',
+            'message' => __('api.mail.test_sent'),
             'recipient' => $recipient,
             'tenant_code' => $tenant->codigo,
             'mailer' => $mailService->mailerName(),
diff --git a/app/Domains/Menu/Models/Menu.php b/app/Domains/Menu/Models/Menu.php
index de3eaee..26a1a77 100644
--- a/app/Domains/Menu/Models/Menu.php
+++ b/app/Domains/Menu/Models/Menu.php
@@ -48,7 +48,7 @@ class Menu extends Model
                 && empty($menu->static_content_schema)
             ) {
                 throw ValidationException::withMessages([
-                    'static_content_schema' => 'El schema es obligatorio para los menús estáticos.',
+                    'static_content_schema' => __('api.menu.schema_required'),
                 ]);
             }
         });
diff --git a/app/Domains/Menu/Requests/StoreTenantMenuRequest.php b/app/Domains/Menu/Requests/StoreTenantMenuRequest.php
index abc2e1f..0ee9b99 100644
--- a/app/Domains/Menu/Requests/StoreTenantMenuRequest.php
+++ b/app/Domains/Menu/Requests/StoreTenantMenuRequest.php
@@ -23,7 +23,7 @@ class StoreTenantMenuRequest extends FormRequest
 
         if (! $this->menuModel) {
             throw ValidationException::withMessages([
-                'menu_code' => 'El menú indicado no existe.',
+                'menu_code' => __('api.menu.not_found'),
             ]);
         }
     }
diff --git a/app/Domains/Purchase/Controllers/PurchaseController.php b/app/Domains/Purchase/Controllers/PurchaseController.php
index a02f034..a92e6af 100644
--- a/app/Domains/Purchase/Controllers/PurchaseController.php
+++ b/app/Domains/Purchase/Controllers/PurchaseController.php
@@ -135,7 +135,7 @@ class PurchaseController extends Controller
 
         if ($updated === 0) {
             throw ValidationException::withMessages([
-                'purchase' => 'The purchase is no longer available for payment.',
+                'purchase' => __('api.purchase.not_available_for_payment'),
             ]);
         }
 
@@ -159,8 +159,14 @@ class PurchaseController extends Controller
                     ],
                 ]);
             } catch (\Exception $e) {
+                Log::error('Unable to retrieve TelePagos account information.', [
+                    'purchase_id' => $compra->id,
+                    'exception' => $e,
+                ]);
+
                 return response()->json([
-                    'message' => 'Error getting account info: '.$e->getMessage(),
+                    'code' => 'integration.account_info_failed',
+                    'message' => __('api.integration.account_info_failed'),
                 ], 500);
             }
         }
@@ -182,8 +188,14 @@ class PurchaseController extends Controller
                     'qr_code' => $qrResponse['qr_code'] ?? '',
                 ]);
             } catch (\Exception $e) {
+                Log::error('Unable to generate TelePagos QR code.', [
+                    'purchase_id' => $compra->id,
+                    'exception' => $e,
+                ]);
+
                 return response()->json([
-                    'message' => 'Error generating QR: '.$e->getMessage(),
+                    'code' => 'integration.qr_generation_failed',
+                    'message' => __('api.integration.qr_generation_failed'),
                 ], 500);
             }
 
@@ -197,7 +209,8 @@ class PurchaseController extends Controller
         }
 
         return response()->json([
-            'message' => 'Invalid payment method.',
+            'code' => 'integration.invalid_payment_method',
+            'message' => __('api.integration.invalid_payment_method'),
         ], 400);
     }
 
@@ -222,7 +235,7 @@ class PurchaseController extends Controller
     protected function resolveScopedPurchase(Tenant $tenant, int $userId, Purchase $purchase): Purchase
     {
         if ($purchase->tenant_codigo !== $tenant->codigo || $purchase->user_id !== $userId) {
-            throw new NotFoundHttpException('Purchase not found for tenant.');
+            throw new NotFoundHttpException(__('api.errors.not_found'));
         }
 
         return $purchase;
diff --git a/app/Domains/Purchase/Services/CheckoutService.php b/app/Domains/Purchase/Services/CheckoutService.php
index e2707f3..7a150e9 100644
--- a/app/Domains/Purchase/Services/CheckoutService.php
+++ b/app/Domains/Purchase/Services/CheckoutService.php
@@ -41,7 +41,7 @@ class CheckoutService
 
             if ($cartId === null) {
                 throw ValidationException::withMessages([
-                    'cart_id' => 'A cart or direct item is required.',
+                    'cart_id' => __('api.purchase.source_required'),
                 ]);
             }
 
@@ -64,7 +64,7 @@ class CheckoutService
 
             if ($purchase->payment_method === null) {
                 throw ValidationException::withMessages([
-                    'payment_method' => 'The purchase payment method must be selected before finalizing.',
+                    'payment_method' => __('api.purchase.payment_method_required'),
                 ]);
             }
 
@@ -102,7 +102,7 @@ class CheckoutService
                 || ($purchase->expires_at !== null && $purchase->expires_at->isPast())
             ) {
                 throw ValidationException::withMessages([
-                    'purchase' => 'The purchase is no longer editable.',
+                    'purchase' => __('api.purchase.not_editable'),
                 ]);
             }
 
@@ -128,7 +128,7 @@ class CheckoutService
                 || ($purchase->expires_at !== null && $purchase->expires_at->isPast())
             ) {
                 throw ValidationException::withMessages([
-                    'purchase' => 'The purchase is no longer editable.',
+                    'purchase' => __('api.purchase.not_editable'),
                 ]);
             }
 
@@ -144,7 +144,7 @@ class CheckoutService
 
             if ($purchaseItem->reservation_status !== PurchaseItem::RESERVATION_ACTIVE) {
                 throw ValidationException::withMessages([
-                    'item' => 'The purchase item is no longer editable.',
+                    'item' => __('api.purchase.item_not_editable'),
                 ]);
             }
 
@@ -162,7 +162,7 @@ class CheckoutService
                     }
                 } catch (\InvalidArgumentException $exception) {
                     throw ValidationException::withMessages([
-                        'quantity' => 'No hay suficiente stock disponible.',
+                        'quantity' => __('api.purchase.insufficient_stock'),
                     ]);
                 }
 
@@ -197,7 +197,7 @@ class CheckoutService
                 || ($purchase->expires_at !== null && $purchase->expires_at->isPast())
             ) {
                 throw ValidationException::withMessages([
-                    'purchase' => 'The purchase is no longer editable.',
+                    'purchase' => __('api.purchase.not_editable'),
                 ]);
             }
 
@@ -233,7 +233,7 @@ class CheckoutService
                 Purchase::STATUS_EXPIRED,
             ], true)) {
                 throw ValidationException::withMessages([
-                    'purchase' => 'A cancelled, rejected or expired purchase cannot be confirmed.',
+                    'purchase' => __('api.purchase.cannot_confirm'),
                 ]);
             }
 
@@ -249,7 +249,7 @@ class CheckoutService
                     $this->catalogInventoryService->commit($selection, (int) $item->cantidad);
                 } catch (\InvalidArgumentException $exception) {
                     throw ValidationException::withMessages([
-                        'items' => 'The purchase has an inconsistent stock reservation.',
+                        'items' => __('api.purchase.inconsistent_reservation'),
                     ]);
                 }
 
@@ -306,7 +306,7 @@ class CheckoutService
                 }
 
                 throw ValidationException::withMessages([
-                    'purchase' => 'A paid purchase cannot be cancelled.',
+                    'purchase' => __('api.purchase.paid_cannot_cancel'),
                 ]);
             }
 
@@ -339,7 +339,7 @@ class CheckoutService
                         $this->catalogInventoryService->release($selection, (int) $item->cantidad);
                     } catch (\InvalidArgumentException $exception) {
                         throw ValidationException::withMessages([
-                            'items' => 'The purchase has an inconsistent stock reservation.',
+                            'items' => __('api.purchase.inconsistent_reservation'),
                         ]);
                     }
                 }
@@ -375,7 +375,7 @@ class CheckoutService
 
         if ($availableQuantity !== null && $availableQuantity < $quantity) {
             throw ValidationException::withMessages([
-                'direct_item.cantidad' => "Stock insuficiente. Maximo disponible: {$availableQuantity}.",
+                'direct_item.cantidad' => __('api.purchase.direct_item_max_stock', ['max' => $availableQuantity]),
             ]);
         }
 
@@ -383,7 +383,7 @@ class CheckoutService
             $this->catalogInventoryService->reserve($selection, $quantity);
         } catch (\InvalidArgumentException $exception) {
             throw ValidationException::withMessages([
-                'direct_item.cantidad' => 'No hay suficiente stock disponible.',
+                'direct_item.cantidad' => __('api.purchase.insufficient_stock'),
             ]);
         }
 
@@ -416,7 +416,7 @@ class CheckoutService
 
         if ($cartItems->isEmpty()) {
             throw ValidationException::withMessages([
-                'cart_id' => 'The selected cart does not contain items.',
+                'cart_id' => __('api.purchase.empty_cart'),
             ]);
         }
 
@@ -596,13 +596,13 @@ class CheckoutService
         foreach ($cartItems as $item) {
             if ($item->selectedItem() === null) {
                 throw ValidationException::withMessages([
-                    'cart_id' => 'One or more catalog items could not be loaded.',
+                    'cart_id' => __('api.purchase.catalog_item_missing'),
                 ]);
             }
 
             if ($item->catalogItem?->tenant_code !== $tenant->codigo) {
                 throw ValidationException::withMessages([
-                    'cart_id' => 'One or more catalog items do not belong to the tenant.',
+                    'cart_id' => __('api.purchase.catalog_item_wrong_tenant'),
                 ]);
             }
         }
@@ -621,7 +621,7 @@ class CheckoutService
 
         if ($cart->status !== 'active') {
             throw ValidationException::withMessages([
-                'cart_id' => 'The selected cart is no longer active.',
+                'cart_id' => __('api.purchase.inactive_cart'),
             ]);
         }
 
@@ -682,13 +682,13 @@ class CheckoutService
         if ($catalogItem->isBundle()) {
             if ($variantId !== null) {
                 throw ValidationException::withMessages([
-                    'direct_item.variant_id' => 'Un bundle no admite una variante.',
+                    'direct_item.variant_id' => __('api.cart.bundle_variant_forbidden'),
                 ]);
             }
 
             if (! $catalogItem->bundleComponents()->exists()) {
                 throw ValidationException::withMessages([
-                    'direct_item.catalog_item_id' => 'El bundle no tiene componentes.',
+                    'direct_item.catalog_item_id' => __('api.cart.empty_bundle'),
                 ]);
             }
 
@@ -698,7 +698,7 @@ class CheckoutService
         if ($variantId === null) {
             if ($catalogItem->inventory_id === null) {
                 throw ValidationException::withMessages([
-                    'direct_item.variant_id' => 'Debe seleccionar una variante para este item.',
+                    'direct_item.variant_id' => __('api.cart.variant_required'),
                 ]);
             }
 
diff --git a/app/Domains/Tenant/Services/TenantService.php b/app/Domains/Tenant/Services/TenantService.php
index 9cfc5b4..1ce024d 100644
--- a/app/Domains/Tenant/Services/TenantService.php
+++ b/app/Domains/Tenant/Services/TenantService.php
@@ -225,7 +225,7 @@ class TenantService
             if ($attachment === null) {
                 throw ValidationException::withMessages([
                     "main_carousel_images.{$order}" => [
-                        'La imagen indicada no existe o no es un attachment de tipo imagen.',
+                        __('api.tenant.invalid_carousel_image'),
                     ],
                 ]);
             }
diff --git a/app/Domains/Ticket/Controllers/TicketController.php b/app/Domains/Ticket/Controllers/TicketController.php
index 9c118a8..7562b47 100644
--- a/app/Domains/Ticket/Controllers/TicketController.php
+++ b/app/Domains/Ticket/Controllers/TicketController.php
@@ -3,6 +3,7 @@
 namespace App\Domains\Ticket\Controllers;
 
 use App\Domains\Tenant\Models\Tenant;
+use App\Domains\Ticket\Exceptions\TicketNotAvailableException;
 use App\Domains\Ticket\Models\Ticket;
 use App\Domains\Ticket\Requests\DownloadTicketsPdfRequest;
 use App\Domains\Ticket\Resources\TicketResource;
@@ -37,11 +38,9 @@ class TicketController extends Controller
             ->orderByDesc('id')
             ->get();
 
-        abort_if(
-            $tickets->count() !== count($ticketIds),
-            404,
-            'Uno o más tickets no están disponibles.'
-        );
+        if ($tickets->count() !== count($ticketIds)) {
+            throw new TicketNotAvailableException(__('api.ticket.not_available'));
+        }
 
         return $this->ticketPdfService->download($tenant, $tickets);
     }
diff --git a/app/Domains/Ticket/Exceptions/TicketGenerationException.php b/app/Domains/Ticket/Exceptions/TicketGenerationException.php
index 94c44a0..e9fa303 100644
--- a/app/Domains/Ticket/Exceptions/TicketGenerationException.php
+++ b/app/Domains/Ticket/Exceptions/TicketGenerationException.php
@@ -11,22 +11,22 @@ class TicketGenerationException extends RuntimeException
 {
     public static function invalidQuantity(): self
     {
-        return new self('La cantidad de tickets a generar debe ser mayor a cero.');
+        return new self(__('api.ticket.positive_quantity'));
     }
 
     public static function emptyBundle(CatalogItem $bundle): self
     {
-        return new self("El bundle {$bundle->id} no tiene componentes.");
+        return new self(__('api.ticket.empty_bundle', ['bundle' => $bundle->id]));
     }
 
     public static function ticketsDisabled(CatalogItem $catalogItem): self
     {
-        return new self("El producto {$catalogItem->id} no tiene tickets habilitados.");
+        return new self(__('api.ticket.disabled', ['product' => $catalogItem->id]));
     }
 
     public static function maximumUseDateReached(CatalogItem $catalogItem): self
     {
-        return new self("El producto {$catalogItem->id} alcanzó su fecha máxima de uso.");
+        return new self(__('api.ticket.expired', ['product' => $catalogItem->id]));
     }
 
     public static function variantNotFound(
@@ -34,17 +34,20 @@ class TicketGenerationException extends RuntimeException
         int $variantId,
     ): self {
         return new self(
-            "La variante {$variantId} no pertenece al producto {$catalogItem->id}.",
+            __('api.ticket.invalid_variant', [
+                'variant' => $variantId,
+                'product' => $catalogItem->id,
+            ]),
         );
     }
 
     public static function purchaseWithoutUser(Purchase $purchase): self
     {
-        return new self("La compra {$purchase->id} no tiene un usuario asociado.");
+        return new self(__('api.ticket.purchase_without_user', ['purchase' => $purchase->id]));
     }
 
     public static function catalogItemNotFound(PurchaseItem $purchaseItem): self
     {
-        return new self("No se encontró el producto de la línea de compra {$purchaseItem->id}.");
+        return new self(__('api.ticket.product_not_found', ['purchase_item' => $purchaseItem->id]));
     }
 }
diff --git a/app/Domains/Ticket/Exceptions/TicketNotAvailableException.php b/app/Domains/Ticket/Exceptions/TicketNotAvailableException.php
new file mode 100644
index 0000000..7fac93e
--- /dev/null
+++ b/app/Domains/Ticket/Exceptions/TicketNotAvailableException.php
@@ -0,0 +1,7 @@
+<?php
+
+namespace App\Domains\Ticket\Exceptions;
+
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+class TicketNotAvailableException extends NotFoundHttpException {}
diff --git a/app/Http/Middleware/SetApiLocale.php b/app/Http/Middleware/SetApiLocale.php
new file mode 100644
index 0000000..cde8890
--- /dev/null
+++ b/app/Http/Middleware/SetApiLocale.php
@@ -0,0 +1,33 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\App;
+use Symfony\Component\HttpFoundation\Response;
+
+class SetApiLocale
+{
+    public function handle(Request $request, Closure $next): Response
+    {
+        if (! $request->is('api/*')) {
+            return $next($request);
+        }
+
+        $supportedLocales = config('app.supported_locales', ['es', 'en']);
+        $acceptLanguage = $request->header('Accept-Language');
+        $locale = is_string($acceptLanguage) && $acceptLanguage !== ''
+            ? $request->getPreferredLanguage($supportedLocales)
+            : null;
+        $locale ??= config('app.locale', 'es');
+
+        App::setLocale($locale);
+
+        $response = $next($request);
+        $response->headers->set('Content-Language', $locale);
+        $response->setVary('Accept-Language', false);
+
+        return $response;
+    }
+}
diff --git a/bootstrap/app.php b/bootstrap/app.php
index 8a4fa0e..e5122d6 100644
--- a/bootstrap/app.php
+++ b/bootstrap/app.php
@@ -1,9 +1,16 @@
 <?php
 
+use App\Domains\Ticket\Exceptions\TicketNotAvailableException;
+use App\Http\Middleware\SetApiLocale;
+use Illuminate\Auth\Access\AuthorizationException;
+use Illuminate\Auth\AuthenticationException;
+use Illuminate\Database\Eloquent\ModelNotFoundException;
 use Illuminate\Foundation\Application;
 use Illuminate\Foundation\Configuration\Exceptions;
 use Illuminate\Foundation\Configuration\Middleware;
 use Illuminate\Http\Request;
+use Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 
 return Application::configure(basePath: dirname(__DIR__))
     ->withRouting(
@@ -16,9 +23,70 @@ return Application::configure(basePath: dirname(__DIR__))
         $middleware->encryptCookies(except: [
             'guest_token',
         ]);
+        $middleware->prepend(SetApiLocale::class);
     })
     ->withExceptions(function (Exceptions $exceptions): void {
         $exceptions->shouldRenderJsonWhen(
             fn (Request $request) => $request->is('api/*'),
         );
+        $exceptions->render(function (AuthenticationException $exception, Request $request) {
+            if (! $request->is('api/*')) {
+                return null;
+            }
+
+            return response()->json([
+                'code' => 'auth.unauthenticated',
+                'message' => __('api.auth.unauthenticated'),
+            ], 401);
+        });
+        $exceptions->render(function (AuthorizationException $exception, Request $request) {
+            if (! $request->is('api/*')) {
+                return null;
+            }
+
+            return response()->json([
+                'code' => 'errors.forbidden',
+                'message' => __('api.errors.forbidden'),
+            ], 403);
+        });
+        $exceptions->render(function (ModelNotFoundException $exception, Request $request) {
+            if (! $request->is('api/*')) {
+                return null;
+            }
+
+            return response()->json([
+                'code' => 'errors.not_found',
+                'message' => __('api.errors.not_found'),
+            ], 404);
+        });
+        $exceptions->render(function (TicketNotAvailableException $exception, Request $request) {
+            if (! $request->is('api/*')) {
+                return null;
+            }
+
+            return response()->json([
+                'code' => 'ticket.not_available',
+                'message' => __('api.ticket.not_available'),
+            ], 404);
+        });
+        $exceptions->render(function (NotFoundHttpException $exception, Request $request) {
+            if (! $request->is('api/*')) {
+                return null;
+            }
+
+            return response()->json([
+                'code' => 'errors.not_found',
+                'message' => __('api.errors.not_found'),
+            ], 404);
+        });
+        $exceptions->render(function (MethodNotAllowedHttpException $exception, Request $request) {
+            if (! $request->is('api/*')) {
+                return null;
+            }
+
+            return response()->json([
+                'code' => 'errors.method_not_allowed',
+                'message' => __('api.errors.method_not_allowed'),
+            ], 405, $exception->getHeaders());
+        });
     })->create();
diff --git a/config/app.php b/config/app.php
index 423eed5..722f90d 100644
--- a/config/app.php
+++ b/config/app.php
@@ -78,9 +78,11 @@ return [
     |
     */
 
-    'locale' => env('APP_LOCALE', 'en'),
+    'locale' => env('APP_LOCALE', 'es'),
 
-    'fallback_locale' => env('APP_FALLBACK_LOCALE', 'en'),
+    'fallback_locale' => env('APP_FALLBACK_LOCALE', 'es'),
+
+    'supported_locales' => ['es', 'en'],
 
     'faker_locale' => env('APP_FAKER_LOCALE', 'en_US'),
 
diff --git a/lang/en/api.php b/lang/en/api.php
new file mode 100644
index 0000000..4f491f3
--- /dev/null
+++ b/lang/en/api.php
@@ -0,0 +1,104 @@
+<?php
+
+return [
+    'auth' => [
+        'unauthenticated' => 'Unauthenticated.',
+        'invalid_credentials' => 'Email or password is incorrect.',
+        'login_success' => 'Signed in successfully.',
+        'logout_success' => 'Signed out successfully.',
+        'register_success' => 'User registered successfully.',
+        'password_reset_requested' => 'If the email is registered, you will receive a code to reset your password.',
+        'password_reset_invalid' => 'The password recovery request is invalid or has already been used.',
+        'password_updated' => 'Password updated successfully.',
+        'reset_code_invalid' => 'The code you entered is invalid.',
+        'reset_code_valid' => 'Code validated successfully.',
+        'invalid_tenant_or_return_url' => 'The tenant or return URL is invalid.',
+        'request_expired' => 'The authentication request expired. Please try again.',
+        'invalid_return_url' => 'The return URL is invalid.',
+        'oauth_code_expired' => 'The authentication code expired or has already been used.',
+        'tenant_mismatch' => 'The tenant does not match the authentication request.',
+        'google_email_required' => 'Google did not return an email for the account.',
+        'google_email_unverified' => 'The Google account must have a verified email.',
+    ],
+    'cart' => [
+        'item_added' => 'Product added to cart.',
+        'quantity_updated' => 'Product quantity updated.',
+        'item_removed' => 'Product removed from cart.',
+        'positive_quantity' => 'The quantity must be greater than zero.',
+        'insufficient_stock' => 'There is not enough stock for the requested product. Maximum available: :max.',
+        'max_quantity' => 'You can add a maximum of :max.',
+        'bundle_variant_forbidden' => 'A bundle cannot have a variant.',
+        'empty_bundle' => 'The bundle has no components.',
+        'variant_required' => 'You must select a variant for this item.',
+    ],
+    'purchase' => [
+        'source_required' => 'A cart or direct item is required.',
+        'payment_method_required' => 'The purchase payment method must be selected before finalizing.',
+        'not_editable' => 'The purchase is no longer editable.',
+        'item_not_editable' => 'The purchase item is no longer editable.',
+        'insufficient_stock' => 'There is not enough stock available.',
+        'cannot_confirm' => 'A cancelled, rejected, or expired purchase cannot be confirmed.',
+        'inconsistent_reservation' => 'The purchase has an inconsistent stock reservation.',
+        'paid_cannot_cancel' => 'A paid purchase cannot be cancelled.',
+        'direct_item_max_stock' => 'There is not enough stock. Maximum available: :max.',
+        'empty_cart' => 'The selected cart does not contain items.',
+        'catalog_item_missing' => 'One or more catalog items could not be loaded.',
+        'catalog_item_wrong_tenant' => 'One or more catalog items do not belong to the tenant.',
+        'inactive_cart' => 'The selected cart is no longer active.',
+        'not_available_for_payment' => 'The purchase is no longer available for payment.',
+    ],
+    'ticket' => [
+        'not_available' => 'One or more tickets are not available.',
+        'positive_quantity' => 'The number of tickets to generate must be greater than zero.',
+        'empty_bundle' => 'Bundle :bundle has no components.',
+        'disabled' => 'Product :product does not have tickets enabled.',
+        'expired' => 'Product :product has reached its maximum usage date.',
+        'invalid_variant' => 'Variant :variant does not belong to product :product.',
+        'purchase_without_user' => 'Purchase :purchase does not have an associated user.',
+        'product_not_found' => 'The product for purchase item :purchase_item was not found.',
+    ],
+    'integration' => [
+        'not_configured' => 'The integration is not configured for this tenant.',
+        'configured' => 'Integration configured successfully.',
+        'validation_failed' => 'Configuration validation failed: :error',
+        'invalid_payment_method' => 'Invalid payment method.',
+        'account_info_failed' => 'Could not retrieve account information.',
+        'qr_generation_failed' => 'Could not generate the QR code.',
+        'webhook_failed' => 'The webhook could not be processed.',
+    ],
+    'mail' => [
+        'test_sent' => 'Test email sent successfully.',
+    ],
+    'catalog' => [
+        'standard_with_components' => 'A standard item cannot have components.',
+        'duplicate_component' => 'The component is duplicated.',
+        'component_wrong_tenant' => 'The item does not belong to the bundle tenant.',
+        'invalid_component' => 'The component must be a standard item other than the bundle.',
+        'component_variant_required' => 'You must select a variant for this component.',
+        'component_variant_forbidden' => 'A component with direct inventory cannot have a variant.',
+        'component_variant_invalid' => 'The variant does not belong to the selected component.',
+        'bundle_component_required' => 'A bundle must have at least one component.',
+        'bundle_field_forbidden' => ':field is not allowed for a bundle.',
+        'attachment_not_found' => 'The specified attachment does not exist.',
+        'attribute_not_found' => 'Attribute :attribute does not exist for the item tenant.',
+        'managed_inventory_fields' => 'inventory_id, reserved_stock, and sold_units are managed internally.',
+        'attribute_not_on_item' => 'The attribute does not belong to the catalog item.',
+        'invalid_effective_date_range' => 'The effective maximum date must be after or equal to the effective minimum date.',
+        'variants_required' => 'An item with attribute_codes must have variants.',
+        'variants_forbidden' => 'An item without attribute_codes cannot have variants.',
+        'direct_inventory_forbidden' => 'An item with variants cannot have direct inventory.',
+    ],
+    'menu' => [
+        'schema_required' => 'The schema is required for static menus.',
+        'not_found' => 'The specified menu does not exist.',
+    ],
+    'tenant' => [
+        'invalid_carousel_image' => 'The specified image does not exist or is not an image attachment.',
+    ],
+    'errors' => [
+        'forbidden' => 'You do not have permission to perform this action.',
+        'not_found' => 'The requested resource was not found.',
+        'method_not_allowed' => 'The HTTP method is not allowed for this route.',
+        'request_failed' => 'The request could not be processed.',
+    ],
+];
diff --git a/lang/en/validation.php b/lang/en/validation.php
new file mode 100644
index 0000000..8476649
--- /dev/null
+++ b/lang/en/validation.php
@@ -0,0 +1,57 @@
+<?php
+
+return [
+    'after_or_equal' => 'The :attribute must be a date after or equal to :date.',
+    'array' => 'The :attribute must be an array.',
+    'boolean' => 'The :attribute field must be true or false.',
+    'confirmed' => 'The :attribute confirmation does not match.',
+    'date' => 'The :attribute must be a valid date.',
+    'distinct' => 'The :attribute field has a duplicate value.',
+    'email' => 'The :attribute must be a valid email address.',
+    'exists' => 'The selected :attribute is invalid.',
+    'file' => 'The :attribute must be a file.',
+    'integer' => 'The :attribute must be an integer.',
+    'max' => [
+        'array' => 'The :attribute must not have more than :max items.',
+        'file' => 'The :attribute must not be greater than :max kilobytes.',
+        'numeric' => 'The :attribute must not be greater than :max.',
+        'string' => 'The :attribute must not be greater than :max characters.',
+    ],
+    'min' => [
+        'array' => 'The :attribute must have at least :min items.',
+        'file' => 'The :attribute must be at least :min kilobytes.',
+        'numeric' => 'The :attribute must be at least :min.',
+        'string' => 'The :attribute must be at least :min characters.',
+    ],
+    'numeric' => 'The :attribute must be a number.',
+    'password' => [
+        'letters' => 'The :attribute must contain at least one letter.',
+        'mixed' => 'The :attribute must contain at least one uppercase and one lowercase letter.',
+        'numbers' => 'The :attribute must contain at least one number.',
+        'symbols' => 'The :attribute must contain at least one symbol.',
+        'uncompromised' => 'The given :attribute has appeared in a data leak. Please choose a different one.',
+    ],
+    'prohibited' => 'The :attribute field is prohibited.',
+    'regex' => 'The :attribute format is invalid.',
+    'required' => 'The :attribute field is required.',
+    'required_with' => 'The :attribute field is required when :values is present.',
+    'required_without' => 'The :attribute field is required when :values is not present.',
+    'string' => 'The :attribute must be a string.',
+    'unique' => 'The :attribute has already been taken.',
+    'url' => 'The :attribute must be a valid URL.',
+    'uuid' => 'The :attribute must be a valid UUID.',
+    'attributes' => [
+        'cantidad' => 'quantity',
+        'catalog_item_id' => 'product',
+        'codigo' => 'code',
+        'dni' => 'ID number',
+        'email' => 'email',
+        'nombre_apellido' => 'full name',
+        'oauth_code' => 'authentication code',
+        'password' => 'password',
+        'password_confirmation' => 'password confirmation',
+        'telefono' => 'phone number',
+        'tenant_codigo' => 'tenant',
+        'variant_id' => 'variant',
+    ],
+];
diff --git a/lang/es/api.php b/lang/es/api.php
new file mode 100644
index 0000000..19a3c67
--- /dev/null
+++ b/lang/es/api.php
@@ -0,0 +1,104 @@
+<?php
+
+return [
+    'auth' => [
+        'unauthenticated' => 'No autenticado.',
+        'invalid_credentials' => 'Email o contraseña incorrectos.',
+        'login_success' => 'Sesión iniciada correctamente.',
+        'logout_success' => 'Sesión cerrada correctamente.',
+        'register_success' => 'Usuario registrado correctamente.',
+        'password_reset_requested' => 'Si el email está registrado, recibirás un código para recuperar tu contraseña.',
+        'password_reset_invalid' => 'La solicitud de recuperación es inválida o ya fue utilizada.',
+        'password_updated' => 'Contraseña modificada correctamente.',
+        'reset_code_invalid' => 'El código ingresado es inválido.',
+        'reset_code_valid' => 'Código validado correctamente.',
+        'invalid_tenant_or_return_url' => 'El tenant o la URL de retorno no son válidos.',
+        'request_expired' => 'La solicitud de autenticación expiró. Intenta nuevamente.',
+        'invalid_return_url' => 'La URL de retorno no es válida.',
+        'oauth_code_expired' => 'El código de autenticación expiró o ya fue utilizado.',
+        'tenant_mismatch' => 'El tenant no coincide con la solicitud de autenticación.',
+        'google_email_required' => 'Google no devolvió un email para la cuenta.',
+        'google_email_unverified' => 'La cuenta de Google debe tener el email verificado.',
+    ],
+    'cart' => [
+        'item_added' => 'Producto agregado al carrito.',
+        'quantity_updated' => 'Cantidad de producto actualizada.',
+        'item_removed' => 'Producto eliminado del carrito.',
+        'positive_quantity' => 'La cantidad debe ser mayor a cero.',
+        'insufficient_stock' => 'Stock insuficiente para el producto solicitado. Máximo disponible: :max.',
+        'max_quantity' => 'El máximo que se puede agregar es :max.',
+        'bundle_variant_forbidden' => 'Un bundle no admite una variante.',
+        'empty_bundle' => 'El bundle no tiene componentes.',
+        'variant_required' => 'Debe seleccionar una variante para este ítem.',
+    ],
+    'purchase' => [
+        'source_required' => 'Se requiere un carrito o un producto directo.',
+        'payment_method_required' => 'Debes seleccionar el método de pago antes de finalizar la compra.',
+        'not_editable' => 'La compra ya no se puede modificar.',
+        'item_not_editable' => 'El producto de la compra ya no se puede modificar.',
+        'insufficient_stock' => 'No hay suficiente stock disponible.',
+        'cannot_confirm' => 'Una compra cancelada, rechazada o vencida no se puede confirmar.',
+        'inconsistent_reservation' => 'La compra tiene una reserva de stock inconsistente.',
+        'paid_cannot_cancel' => 'Una compra pagada no se puede cancelar.',
+        'direct_item_max_stock' => 'Stock insuficiente. Máximo disponible: :max.',
+        'empty_cart' => 'El carrito seleccionado no contiene productos.',
+        'catalog_item_missing' => 'No se pudieron cargar uno o más productos del catálogo.',
+        'catalog_item_wrong_tenant' => 'Uno o más productos no pertenecen al tenant.',
+        'inactive_cart' => 'El carrito seleccionado ya no está activo.',
+        'not_available_for_payment' => 'La compra ya no está disponible para el pago.',
+    ],
+    'ticket' => [
+        'not_available' => 'Uno o más tickets no están disponibles.',
+        'positive_quantity' => 'La cantidad de tickets a generar debe ser mayor a cero.',
+        'empty_bundle' => 'El bundle :bundle no tiene componentes.',
+        'disabled' => 'El producto :product no tiene tickets habilitados.',
+        'expired' => 'El producto :product alcanzó su fecha máxima de uso.',
+        'invalid_variant' => 'La variante :variant no pertenece al producto :product.',
+        'purchase_without_user' => 'La compra :purchase no tiene un usuario asociado.',
+        'product_not_found' => 'No se encontró el producto de la línea de compra :purchase_item.',
+    ],
+    'integration' => [
+        'not_configured' => 'La integración no está configurada para este tenant.',
+        'configured' => 'Integración configurada correctamente.',
+        'validation_failed' => 'Error validando la configuración: :error',
+        'invalid_payment_method' => 'Método de pago inválido.',
+        'account_info_failed' => 'No se pudo obtener la información de la cuenta.',
+        'qr_generation_failed' => 'No se pudo generar el código QR.',
+        'webhook_failed' => 'No se pudo procesar el webhook.',
+    ],
+    'mail' => [
+        'test_sent' => 'Correo de prueba enviado correctamente.',
+    ],
+    'catalog' => [
+        'standard_with_components' => 'Un ítem standard no puede tener componentes.',
+        'duplicate_component' => 'El componente está duplicado.',
+        'component_wrong_tenant' => 'El ítem no pertenece al tenant del bundle.',
+        'invalid_component' => 'El componente debe ser un ítem standard distinto del bundle.',
+        'component_variant_required' => 'Debe seleccionar una variante para este componente.',
+        'component_variant_forbidden' => 'El componente con inventario directo no admite una variante.',
+        'component_variant_invalid' => 'La variante no pertenece al componente indicado.',
+        'bundle_component_required' => 'Un bundle debe tener al menos un componente.',
+        'bundle_field_forbidden' => ':field no se admite para un bundle.',
+        'attachment_not_found' => 'El attachment indicado no existe.',
+        'attribute_not_found' => 'El atributo :attribute no existe para el tenant del ítem.',
+        'managed_inventory_fields' => 'inventory_id, reserved_stock y sold_units son administrados internamente.',
+        'attribute_not_on_item' => 'El atributo no pertenece al ítem de catálogo.',
+        'invalid_effective_date_range' => 'La fecha máxima efectiva debe ser posterior o igual a la fecha mínima efectiva.',
+        'variants_required' => 'Un ítem con attribute_codes debe tener variantes.',
+        'variants_forbidden' => 'Un ítem sin attribute_codes no puede tener variantes.',
+        'direct_inventory_forbidden' => 'Un ítem con variantes no puede tener inventario directo.',
+    ],
+    'menu' => [
+        'schema_required' => 'El schema es obligatorio para los menús estáticos.',
+        'not_found' => 'El menú indicado no existe.',
+    ],
+    'tenant' => [
+        'invalid_carousel_image' => 'La imagen indicada no existe o no es un attachment de tipo imagen.',
+    ],
+    'errors' => [
+        'forbidden' => 'No tienes permiso para realizar esta acción.',
+        'not_found' => 'El recurso solicitado no fue encontrado.',
+        'method_not_allowed' => 'El método HTTP no está permitido para esta ruta.',
+        'request_failed' => 'No se pudo procesar la solicitud.',
+    ],
+];
diff --git a/lang/es/validation.php b/lang/es/validation.php
new file mode 100644
index 0000000..7aa7787
--- /dev/null
+++ b/lang/es/validation.php
@@ -0,0 +1,57 @@
+<?php
+
+return [
+    'after_or_equal' => ':Attribute debe ser una fecha posterior o igual a :date.',
+    'array' => ':Attribute debe ser un arreglo.',
+    'boolean' => 'El campo :attribute debe ser verdadero o falso.',
+    'confirmed' => 'La confirmación de :attribute no coincide.',
+    'date' => ':Attribute no es una fecha válida.',
+    'distinct' => 'El campo :attribute tiene un valor duplicado.',
+    'email' => ':Attribute debe ser una dirección de email válida.',
+    'exists' => 'El valor seleccionado para :attribute no es válido.',
+    'file' => ':Attribute debe ser un archivo.',
+    'integer' => ':Attribute debe ser un número entero.',
+    'max' => [
+        'array' => ':Attribute no debe tener más de :max elementos.',
+        'file' => ':Attribute no debe superar los :max kilobytes.',
+        'numeric' => ':Attribute no debe ser mayor que :max.',
+        'string' => ':Attribute no debe tener más de :max caracteres.',
+    ],
+    'min' => [
+        'array' => ':Attribute debe tener al menos :min elementos.',
+        'file' => ':Attribute debe pesar al menos :min kilobytes.',
+        'numeric' => ':Attribute debe ser al menos :min.',
+        'string' => ':Attribute debe tener al menos :min caracteres.',
+    ],
+    'numeric' => ':Attribute debe ser un número.',
+    'password' => [
+        'letters' => ':Attribute debe contener al menos una letra.',
+        'mixed' => ':Attribute debe contener al menos una letra mayúscula y una minúscula.',
+        'numbers' => ':Attribute debe contener al menos un número.',
+        'symbols' => ':Attribute debe contener al menos un símbolo.',
+        'uncompromised' => ':Attribute aparece en una filtración de datos. Elige una contraseña diferente.',
+    ],
+    'prohibited' => 'El campo :attribute está prohibido.',
+    'regex' => 'El formato de :attribute no es válido.',
+    'required' => 'El campo :attribute es obligatorio.',
+    'required_with' => 'El campo :attribute es obligatorio cuando :values está presente.',
+    'required_without' => 'El campo :attribute es obligatorio cuando :values no está presente.',
+    'string' => ':Attribute debe ser texto.',
+    'unique' => 'El valor de :attribute ya está en uso.',
+    'url' => ':Attribute debe ser una URL válida.',
+    'uuid' => ':Attribute debe ser un UUID válido.',
+    'attributes' => [
+        'cantidad' => 'cantidad',
+        'catalog_item_id' => 'producto',
+        'codigo' => 'código',
+        'dni' => 'DNI',
+        'email' => 'email',
+        'nombre_apellido' => 'nombre y apellido',
+        'oauth_code' => 'código de autenticación',
+        'password' => 'contraseña',
+        'password_confirmation' => 'confirmación de contraseña',
+        'telefono' => 'teléfono',
+        'tenant_codigo' => 'tenant',
+        'variant_id' => 'variante',
+    ],
+];
diff --git a/tests/Feature/Auth/LoginControllerTest.php b/tests/Feature/Auth/LoginControllerTest.php
index 38de2c6..37fd92f 100644
--- a/tests/Feature/Auth/LoginControllerTest.php
+++ b/tests/Feature/Auth/LoginControllerTest.php
@@ -35,7 +35,9 @@ class LoginControllerTest extends TestCase
 
         $response
             ->assertOk()
-            ->assertJsonPath('message', 'Sesion iniciada correctamente.')
+            ->assertHeader('Content-Language', 'es')
+            ->assertJsonPath('code', 'auth.login_success')
+            ->assertJsonPath('message', 'Sesión iniciada correctamente.')
             ->assertJsonPath('token_type', 'Bearer')
             ->assertJsonPath('user.id', $user->id)
             ->assertJsonPath('user.nombre_apellido', 'Grace Hopper')
@@ -85,7 +87,8 @@ class LoginControllerTest extends TestCase
         $this->withHeader('Authorization', 'Bearer '.$token)
             ->postJson('/api/logout')
             ->assertOk()
-            ->assertJsonPath('message', 'Sesion cerrada correctamente.');
+            ->assertJsonPath('code', 'auth.logout_success')
+            ->assertJsonPath('message', 'Sesión cerrada correctamente.');
 
         $this->assertDatabaseCount('personal_access_tokens', 0);
     }
@@ -118,6 +121,34 @@ class LoginControllerTest extends TestCase
         ]);
     }
 
+    public function test_it_localizes_success_and_validation_responses_from_accept_language(): void
+    {
+        $tenant = $this->createTenant('acme');
+        User::query()->create([
+            'nombre_apellido' => 'Grace Hopper',
+            'email' => 'grace@example.com',
+            'password' => Hash::make('secret123'),
+        ]);
+
+        $this->withHeader('Accept-Language', 'en-US,en;q=0.9')
+            ->postJson('/api/login', [
+                'email' => 'grace@example.com',
+                'password' => 'secret123',
+                'tenant_codigo' => $tenant->codigo,
+            ])
+            ->assertOk()
+            ->assertHeader('Content-Language', 'en')
+            ->assertJsonPath('code', 'auth.login_success')
+            ->assertJsonPath('message', 'Signed in successfully.');
+
+        $this->withHeader('Accept-Language', 'en')
+            ->postJson('/api/login', [])
+            ->assertUnprocessable()
+            ->assertHeader('Content-Language', 'en')
+            ->assertJsonPath('errors.email.0', 'The email field is required.')
+            ->assertJsonPath('errors.password.0', 'The password field is required.');
+    }
+
     public function test_it_replaces_the_active_user_cart_with_the_guest_cart_on_login(): void
     {
         $tenant = $this->createTenant('acme');
diff --git a/tests/Feature/Integration/TenantIntegrationControllerTest.php b/tests/Feature/Integration/TenantIntegrationControllerTest.php
index d56be2c..744f3f8 100644
--- a/tests/Feature/Integration/TenantIntegrationControllerTest.php
+++ b/tests/Feature/Integration/TenantIntegrationControllerTest.php
@@ -31,7 +31,7 @@ class TenantIntegrationControllerTest extends TestCase
                     Mockery::on(fn (Integration $argument) => $argument->is($integration)),
                     ['api_key' => 'secret']
                 )
-                ->andReturn(new TenantIntegration());
+                ->andReturn(new TenantIntegration);
         });
 
         $this->postJson('/api/test-tenant/integrations/test_integration', [
@@ -40,7 +40,8 @@ class TenantIntegrationControllerTest extends TestCase
             ],
         ])->assertOk()
             ->assertExactJson([
-                'message' => 'integration configured correctly',
+                'code' => 'integration.configured',
+                'message' => 'Integración configurada correctamente.',
             ]);
     }
 }
diff --git a/tests/Feature/Localization/ApiLocalizationTest.php b/tests/Feature/Localization/ApiLocalizationTest.php
new file mode 100644
index 0000000..ffde69c
--- /dev/null
+++ b/tests/Feature/Localization/ApiLocalizationTest.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace Tests\Feature\Localization;
+
+use Tests\TestCase;
+
+class ApiLocalizationTest extends TestCase
+{
+    public function test_it_negotiates_spanish_from_accept_language(): void
+    {
+        $this->withHeader('Accept-Language', 'es-AR,es;q=0.9')
+            ->postJson('/api/login')
+            ->assertUnprocessable()
+            ->assertHeader('Content-Language', 'es')
+            ->assertJsonPath('errors.email.0', 'El campo email es obligatorio.')
+            ->assertJsonPath('errors.password.0', 'El campo contraseña es obligatorio.');
+    }
+
+    public function test_it_negotiates_english_from_accept_language(): void
+    {
+        $this->withHeader('Accept-Language', 'en-US,en;q=0.9')
+            ->postJson('/api/login')
+            ->assertUnprocessable()
+            ->assertHeader('Content-Language', 'en')
+            ->assertJsonPath('errors.email.0', 'The email field is required.')
+            ->assertJsonPath('errors.password.0', 'The password field is required.');
+    }
+
+    public function test_it_localizes_framework_error_responses(): void
+    {
+        $this->withHeader('Accept-Language', 'en')
+            ->getJson('/api/route-that-does-not-exist')
+            ->assertNotFound()
+            ->assertHeader('Content-Language', 'en')
+            ->assertJson([
+                'code' => 'errors.not_found',
+                'message' => 'The requested resource was not found.',
+            ]);
+    }
+}