diff --git a/api/controllers/console/explore/recommended_app.py b/api/controllers/console/explore/recommended_app.py
index 1125c0bc580..1fdf61f049d 100644
--- a/api/controllers/console/explore/recommended_app.py
+++ b/api/controllers/console/explore/recommended_app.py
@@ -7,17 +7,17 @@ from pydantic import BaseModel, Field, computed_field, field_validator
 from controllers.common.schema import query_params_from_model, register_response_schema_models, register_schema_models
 from controllers.console import console_ns
 from controllers.console.explore.error import RecommendedAppNotFoundError
-from controllers.console.wraps import account_initialization_required, model_validate, with_current_user
+from controllers.console.flask_admission import console_account_admission
+from controllers.console.wraps import model_validate
 from extensions.ext_application_services import application_services
 from fields.base import ResponseModel
 from libs.helper import build_icon_url, dump_response
-from libs.login import login_required
-from models import Account
+from machinery.context import RequestContext
 from services.recommended_app_query_service import RecommendedAppNotFoundError as RecommendedAppQueryNotFoundError
 
 
 class RecommendedAppsQuery(BaseModel):
-    language: str | None = Field(default=None, description="Language code for recommended app localization")
+    language: str = Field(default="en-US", description="Language code for recommended app localization")
 
 
 class RecommendedAppInfoResponse(ResponseModel):
@@ -97,16 +97,13 @@ register_response_schema_models(
 class RecommendedAppListApi(Resource):
     @console_ns.doc(params=query_params_from_model(RecommendedAppsQuery))
     @console_ns.response(200, "Success", console_ns.models[RecommendedAppListResponse.__name__])
-    @login_required
-    @account_initialization_required
-    @with_current_user
+    @console_account_admission()
     @model_validate(RecommendedAppsQuery)
-    def get(self, req_data: RecommendedAppsQuery, current_user: Account):
+    def get(self, req_data: RecommendedAppsQuery, _request_context: RequestContext):
         return dump_response(
             RecommendedAppListResponse,
             application_services().recommended_app_queries.list_recommended(
-                requested_language=req_data.language,
-                interface_language=current_user.interface_language,
+                language=req_data.language,
             ),
         )
 
@@ -115,16 +112,13 @@ class RecommendedAppListApi(Resource):
 class LearnDifyAppListApi(Resource):
     @console_ns.doc(params=query_params_from_model(RecommendedAppsQuery))
     @console_ns.response(200, "Success", console_ns.models[LearnDifyAppListResponse.__name__])
-    @login_required
-    @account_initialization_required
-    @with_current_user
+    @console_account_admission()
     @model_validate(RecommendedAppsQuery)
-    def get(self, req_data: RecommendedAppsQuery, current_user: Account):
+    def get(self, req_data: RecommendedAppsQuery, _request_context: RequestContext):
         return dump_response(
             LearnDifyAppListResponse,
             application_services().recommended_app_queries.list_learn_dify(
-                requested_language=req_data.language,
-                interface_language=current_user.interface_language,
+                language=req_data.language,
             ),
         )
 
@@ -133,9 +127,8 @@ class LearnDifyAppListApi(Resource):
 class RecommendedAppApi(Resource):
     @console_ns.response(200, "Success", console_ns.models[RecommendedAppDetailResponse.__name__])
     @console_ns.response(404, "Recommended app not found")
-    @login_required
-    @account_initialization_required
-    def get(self, app_id: UUID):
+    @console_account_admission()
+    def get(self, _request_context: RequestContext, app_id: UUID):
         try:
             result = application_services().recommended_app_queries.get_detail(str(app_id))
         except RecommendedAppQueryNotFoundError:
diff --git a/api/openapi/markdown/console-openapi.md b/api/openapi/markdown/console-openapi.md
index 70ddbe73455..0fa45b01005 100644
--- a/api/openapi/markdown/console-openapi.md
+++ b/api/openapi/markdown/console-openapi.md
@@ -6507,7 +6507,7 @@ Check if dataset is in use
 
 | Name | Located in | Description | Required | Schema |
 | ---- | ---------- | ----------- | -------- | ------ |
-| language | query | Language code for recommended app localization | No | string |
+| language | query | Language code for recommended app localization | No | string, <br>**Default:** en-US |
 
 #### Responses
 
@@ -6520,7 +6520,7 @@ Check if dataset is in use
 
 | Name | Located in | Description | Required | Schema |
 | ---- | ---------- | ----------- | -------- | ------ |
-| language | query | Language code for recommended app localization | No | string |
+| language | query | Language code for recommended app localization | No | string, <br>**Default:** en-US |
 
 #### Responses
 
@@ -21331,7 +21331,7 @@ Model class for provider quota configuration.
 
 | Name | Type | Description | Required |
 | ---- | ---- | ----------- | -------- |
-| language | string | Language code for recommended app localization | No |
+| language | string, <br>**Default:** en-US | Language code for recommended app localization | No |
 
 #### RedirectResponse
 
diff --git a/api/services/explore_banner_query_service.py b/api/services/explore_banner_query_service.py
index 8ef4f3827f4..4eb204f7d85 100644
--- a/api/services/explore_banner_query_service.py
+++ b/api/services/explore_banner_query_service.py
@@ -7,6 +7,8 @@ from collections.abc import Sequence
 from datetime import datetime
 from typing import Any, NamedTuple, Protocol
 
+from constants.languages import languages
+
 _DEFAULT_LANGUAGE = "en-US"
 
 
@@ -37,6 +39,7 @@ class ExploreBannerQueryService:
         if not self._enabled:
             return ()
 
+        language = language if language in languages else _DEFAULT_LANGUAGE
         banners = tuple(self._banners.list_enabled(language))
         if banners or language == _DEFAULT_LANGUAGE:
             return banners
diff --git a/api/services/recommended_app_query_service.py b/api/services/recommended_app_query_service.py
index 5b79f40d505..f0da2259797 100644
--- a/api/services/recommended_app_query_service.py
+++ b/api/services/recommended_app_query_service.py
@@ -5,6 +5,8 @@ from typing import NamedTuple, Protocol
 
 from constants.languages import languages
 
+_DEFAULT_LANGUAGE = "en-US"
+
 
 class RecommendedAppInfoRecord(NamedTuple):
     id: str
@@ -116,10 +118,9 @@ class RecommendedAppQueryService:
     def list_recommended(
         self,
         *,
-        requested_language: str | None,
-        interface_language: str | None,
+        language: str,
     ) -> RecommendedAppListResult:
-        language = self._resolve_language(requested_language, interface_language)
+        language = language if language in languages else _DEFAULT_LANGUAGE
         page = self._catalog.list_recommended(language)
 
         return RecommendedAppListResult(
@@ -130,10 +131,9 @@ class RecommendedAppQueryService:
     def list_learn_dify(
         self,
         *,
-        requested_language: str | None,
-        interface_language: str | None,
+        language: str,
     ) -> LearnDifyAppListResult:
-        language = self._resolve_language(requested_language, interface_language)
+        language = language if language in languages else _DEFAULT_LANGUAGE
         page = self._catalog.list_learn_dify(language)
         return LearnDifyAppListResult(recommended_apps=self._with_trial_status(page.recommended_apps))
 
@@ -176,11 +176,3 @@ class RecommendedAppQueryService:
             )
             for app in apps
         )
-
-    @staticmethod
-    def _resolve_language(requested_language: str | None, interface_language: str | None) -> str:
-        if requested_language and requested_language in languages:
-            return requested_language
-        if interface_language:
-            return interface_language
-        return languages[0]
diff --git a/api/tests/unit_tests/controllers/console/explore/test_banner.py b/api/tests/unit_tests/controllers/console/explore/test_banner.py
index 5c44ea4b8f5..9ade4ba82ad 100644
--- a/api/tests/unit_tests/controllers/console/explore/test_banner.py
+++ b/api/tests/unit_tests/controllers/console/explore/test_banner.py
@@ -110,7 +110,7 @@ class TestExploreBannerQueryService:
         assert service.list_for_language("fr-FR") == (record,)
         assert banners.requested_languages == ["fr-FR"]
 
-    def test_falls_back_to_en_us(self) -> None:
+    def test_falls_back_to_en_us_when_requested_translation_is_missing(self) -> None:
         record = _record(title="fallback")
         banners = FakeExploreBannerQuery({"en-US": (record,)})
         service = ExploreBannerQueryService(banners=banners, enabled=True)
@@ -118,6 +118,14 @@ class TestExploreBannerQueryService:
         assert service.list_for_language("es-ES") == (record,)
         assert banners.requested_languages == ["es-ES", "en-US"]
 
+    def test_invalid_language_uses_en_us(self) -> None:
+        record = _record(title="fallback")
+        banners = FakeExploreBannerQuery({"en-US": (record,)})
+        service = ExploreBannerQueryService(banners=banners, enabled=True)
+
+        assert service.list_for_language("invalid") == (record,)
+        assert banners.requested_languages == ["en-US"]
+
     def test_does_not_repeat_default_language_query(self) -> None:
         banners = FakeExploreBannerQuery()
         service = ExploreBannerQueryService(banners=banners, enabled=True)
diff --git a/api/tests/unit_tests/controllers/console/explore/test_recommended_app.py b/api/tests/unit_tests/controllers/console/explore/test_recommended_app.py
index fccbba38d6d..e281a22caac 100644
--- a/api/tests/unit_tests/controllers/console/explore/test_recommended_app.py
+++ b/api/tests/unit_tests/controllers/console/explore/test_recommended_app.py
@@ -7,7 +7,7 @@ from flask import Flask
 from pydantic import ValidationError
 
 import controllers.console.explore.recommended_app as module
-from models import Account
+from machinery.context import RequestContext
 from models.model import AppMode, IconType
 from services.recommended_app_query_service import (
     LearnDifyAppListResult,
@@ -21,11 +21,13 @@ from services.recommended_app_query_service import (
 )
 
 
-def make_account(interface_language: str | None) -> Account:
-    account = Account(name="Test User", email="user@example.com")
-    account.id = "account-1"
-    account.interface_language = interface_language
-    return account
+def _request_context() -> RequestContext:
+    return RequestContext(
+        request_id="request-1",
+        trace_id="trace-1",
+        account_id="account-1",
+        active_workspace_id="workspace-1",
+    )
 
 
 class TestRecommendedAppListApi:
@@ -44,17 +46,16 @@ class TestRecommendedAppListApi:
                 return_value=SimpleNamespace(recommended_app_queries=queries),
             ),
         ):
-            result = method(api, module.RecommendedAppsQuery(language="en-US"), make_account("fr-FR"))
+            result = method(api, module.RecommendedAppsQuery(language="en-US"), _request_context())
 
         queries.list_recommended.assert_called_once_with(
-            requested_language="en-US",
-            interface_language="fr-FR",
+            language="en-US",
         )
         assert result == {"recommended_apps": [], "categories": []}
 
 
 class TestLearnDifyAppListApi:
-    def test_get_with_language_param(self, app: Flask) -> None:
+    def test_get_uses_default_language(self, app: Flask) -> None:
         api = module.LearnDifyAppListApi()
         method = unwrap(api.get)
 
@@ -62,18 +63,17 @@ class TestLearnDifyAppListApi:
         queries.list_learn_dify.return_value = LearnDifyAppListResult(recommended_apps=())
 
         with (
-            app.test_request_context("/", query_string={"language": "en-US"}),
+            app.test_request_context("/"),
             patch.object(
                 module,
                 "application_services",
                 return_value=SimpleNamespace(recommended_app_queries=queries),
             ),
         ):
-            result = method(api, module.RecommendedAppsQuery(language="en-US"), make_account("fr-FR"))
+            result = method(api, module.RecommendedAppsQuery(), _request_context())
 
         queries.list_learn_dify.assert_called_once_with(
-            requested_language="en-US",
-            interface_language="fr-FR",
+            language="en-US",
         )
         assert result == {"recommended_apps": []}
 
@@ -102,7 +102,7 @@ class TestRecommendedAppApi:
                 return_value=SimpleNamespace(recommended_app_queries=queries),
             ),
         ):
-            result = method(api, "11111111-1111-1111-1111-111111111111")
+            result = method(api, _request_context(), "11111111-1111-1111-1111-111111111111")
 
         queries.get_detail.assert_called_once_with("11111111-1111-1111-1111-111111111111")
         assert result == {
@@ -130,7 +130,7 @@ class TestRecommendedAppApi:
             ),
         ):
             with pytest.raises(module.RecommendedAppNotFoundError) as exc_info:
-                method(api, "11111111-1111-1111-1111-111111111111")
+                method(api, _request_context(), "11111111-1111-1111-1111-111111111111")
 
         assert exc_info.value.data == {
             "code": "recommended_app_not_found",
diff --git a/api/tests/unit_tests/extensions/test_ext_application_services.py b/api/tests/unit_tests/extensions/test_ext_application_services.py
index 649958ca5bf..39f8f2c10f6 100644
--- a/api/tests/unit_tests/extensions/test_ext_application_services.py
+++ b/api/tests/unit_tests/extensions/test_ext_application_services.py
@@ -721,14 +721,12 @@ def test_build_application_services_wires_dynamic_recommended_catalog(
     )
     with patch.object(recommended_app_catalog_gateway.Path, "read_text", return_value=builtin_payload):
         result = services.recommended_app_queries.list_recommended(
-            requested_language="en-US",
-            interface_language=None,
+            language="en-US",
         )
     assert result.recommended_apps
 
     apply_config_overrides(monkeypatch, HOSTED_FETCH_APP_TEMPLATES_MODE="invalid")
     with pytest.raises(ValueError, match="invalid fetch recommended apps mode: invalid"):
         services.recommended_app_queries.list_recommended(
-            requested_language="en-US",
-            interface_language=None,
+            language="en-US",
         )
diff --git a/api/tests/unit_tests/services/test_recommended_app_query_service.py b/api/tests/unit_tests/services/test_recommended_app_query_service.py
index 09d661b6754..3e762b12167 100644
--- a/api/tests/unit_tests/services/test_recommended_app_query_service.py
+++ b/api/tests/unit_tests/services/test_recommended_app_query_service.py
@@ -2,7 +2,6 @@ from unittest.mock import MagicMock
 
 import pytest
 
-from constants.languages import languages
 from services.recommended_app_query_service import (
     RecommendedAppCatalogPage,
     RecommendedAppDetailRecord,
@@ -83,17 +82,14 @@ def test_is_previewable_falls_back_to_catalog(expected: bool) -> None:
 
 
 @pytest.mark.parametrize(
-    ("requested_language", "interface_language", "expected"),
+    ("language", "expected"),
     [
-        ("en-US", "fr-FR", "en-US"),
-        ("invalid", "fr-FR", "fr-FR"),
-        (None, "custom-language", "custom-language"),
-        (None, None, languages[0]),
+        ("fr-FR", "fr-FR"),
+        ("invalid", "en-US"),
     ],
 )
 def test_list_recommended_resolves_language(
-    requested_language: str | None,
-    interface_language: str | None,
+    language: str,
     expected: str,
 ) -> None:
     catalog = MagicMock()
@@ -101,8 +97,7 @@ def test_list_recommended_resolves_language(
     service, _ = _service(catalog=catalog)
 
     service.list_recommended(
-        requested_language=requested_language,
-        interface_language=interface_language,
+        language=language,
     )
 
     catalog.list_recommended.assert_called_once_with(expected)
@@ -113,7 +108,7 @@ def test_list_recommended_disables_upstream_trial_without_querying_trial_apps()
     catalog.list_recommended.return_value = _page("app-1")
     service, trial_apps = _service(catalog=catalog)
 
-    result = service.list_recommended(requested_language="en-US", interface_language=None)
+    result = service.list_recommended(language="en-US")
 
     assert result.recommended_apps[0].can_trial is False
     trial_apps.existing_ids.assert_not_called()
@@ -130,7 +125,7 @@ def test_list_recommended_enriches_trial_status_in_one_bulk_query() -> None:
         trial_enabled=True,
     )
 
-    result = service.list_recommended(requested_language="en-US", interface_language=None)
+    result = service.list_recommended(language="en-US")
 
     assert [app.can_trial for app in result.recommended_apps] == [True, False]
     trial_apps.existing_ids.assert_called_once_with(["app-1", "app-2"])
@@ -141,9 +136,9 @@ def test_list_learn_dify_does_not_return_categories() -> None:
     catalog.list_learn_dify.return_value = _page(categories=("ignored",))
     service, _ = _service(catalog=catalog)
 
-    result = service.list_learn_dify(requested_language="invalid", interface_language="fr-FR")
+    result = service.list_learn_dify(language="invalid")
 
-    catalog.list_learn_dify.assert_called_once_with("fr-FR")
+    catalog.list_learn_dify.assert_called_once_with("en-US")
     assert result.recommended_apps == ()
     assert not hasattr(result, "categories")
 
diff --git a/packages/contracts/generated/api/console/explore/zod.gen.ts b/packages/contracts/generated/api/console/explore/zod.gen.ts
index 272b2884146..995a5b98a58 100644
--- a/packages/contracts/generated/api/console/explore/zod.gen.ts
+++ b/packages/contracts/generated/api/console/explore/zod.gen.ts
@@ -137,7 +137,7 @@ export const zLearnDifyAppListResponseWritable = z.object({
 })
 
 export const zGetExploreAppsQuery = z.object({
-  language: z.string().optional(),
+  language: z.string().optional().default('en-US'),
 })
 
 /**
@@ -146,7 +146,7 @@ export const zGetExploreAppsQuery = z.object({
 export const zGetExploreAppsResponse = zRecommendedAppListResponse
 
 export const zGetExploreAppsLearnDifyQuery = z.object({
-  language: z.string().optional(),
+  language: z.string().optional().default('en-US'),
 })
 
 /**