diff --git a/.github/workflows/style.yml b/.github/workflows/style.yml
index 4ce121ba60..c40ca5c1ea 100644
--- a/.github/workflows/style.yml
+++ b/.github/workflows/style.yml
@@ -47,6 +47,10 @@ jobs:
         if: steps.changed-files.outputs.any_changed == 'true'
         run: uv run --directory api --dev lint-imports
 
+      - name: Run Response Contract Linter
+        if: steps.changed-files.outputs.any_changed == 'true'
+        run: uv run --project api --dev python api/dev/lint_response_contracts.py --fail-on-mismatch
+
       - name: Run Type Checks
         if: steps.changed-files.outputs.any_changed == 'true'
         run: make type-check-core
diff --git a/api/controllers/console/apikey.py b/api/controllers/console/apikey.py
index 6463b022b5..aca22d5c5a 100644
--- a/api/controllers/console/apikey.py
+++ b/api/controllers/console/apikey.py
@@ -146,7 +146,7 @@ class BaseApiKeyResource(Resource):
         db.session.execute(delete(ApiToken).where(ApiToken.id == api_key_id))
         db.session.commit()
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/apps/<uuid:resource_id>/api-keys")
diff --git a/api/controllers/console/app/annotation.py b/api/controllers/console/app/annotation.py
index cfeaec4af9..bf8b57685f 100644
--- a/api/controllers/console/app/annotation.py
+++ b/api/controllers/console/app/annotation.py
@@ -269,12 +269,12 @@ class AnnotationApi(Resource):
                     "message": "annotation_ids are required if the parameter is provided.",
                 }, 400
 
-            result = AppAnnotationService.delete_app_annotations_in_batch(str(app_id), annotation_ids)
-            return result, 204
+            AppAnnotationService.delete_app_annotations_in_batch(str(app_id), annotation_ids)
+            return "", 204
         # If no annotation_ids are provided, handle clearing all annotations
         else:
             AppAnnotationService.clear_all_annotations(str(app_id))
-            return {"result": "success"}, 204
+            return "", 204
 
 
 @console_ns.route("/apps/<uuid:app_id>/annotations/export")
@@ -335,7 +335,7 @@ class AnnotationUpdateDeleteApi(Resource):
     @edit_permission_required
     def delete(self, app_id: UUID, annotation_id: UUID):
         AppAnnotationService.delete_app_annotation(str(app_id), str(annotation_id))
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/apps/<uuid:app_id>/annotations/batch-import")
diff --git a/api/controllers/console/app/app.py b/api/controllers/console/app/app.py
index 28d16f852b..6026be9bf9 100644
--- a/api/controllers/console/app/app.py
+++ b/api/controllers/console/app/app.py
@@ -633,7 +633,7 @@ class AppApi(Resource):
         app_service = AppService()
         app_service.delete_app(app_model)
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/apps/<uuid:app_id>/copy")
diff --git a/api/controllers/console/app/conversation.py b/api/controllers/console/app/conversation.py
index c7347933cb..1978018366 100644
--- a/api/controllers/console/app/conversation.py
+++ b/api/controllers/console/app/conversation.py
@@ -29,9 +29,6 @@ from fields.conversation_fields import (
 from fields.conversation_fields import (
     ConversationWithSummaryPagination as ConversationWithSummaryPaginationResponse,
 )
-from fields.conversation_fields import (
-    ResultResponse,
-)
 from libs.datetime_utils import naive_utc_now, parse_time_range
 from libs.login import current_account_with_tenant, login_required
 from models import Conversation, EndUser, Message, MessageAnnotation
@@ -77,7 +74,6 @@ register_schema_models(
     ConversationMessageDetailResponse,
     ConversationWithSummaryPaginationResponse,
     ConversationDetailResponse,
-    ResultResponse,
     CompletionConversationQuery,
     ChatConversationQuery,
 )
@@ -194,7 +190,7 @@ class CompletionConversationDetailApi(Resource):
         except ConversationNotExistsError:
             raise NotFound("Conversation Not Exists.")
 
-        return ResultResponse(result="success").model_dump(mode="json"), 204
+        return "", 204
 
 
 @console_ns.route("/apps/<uuid:app_id>/chat-conversations")
@@ -347,7 +343,7 @@ class ChatConversationDetailApi(Resource):
         except ConversationNotExistsError:
             raise NotFound("Conversation Not Exists.")
 
-        return ResultResponse(result="success").model_dump(mode="json"), 204
+        return "", 204
 
 
 def _get_conversation(app_model, conversation_id):
diff --git a/api/controllers/console/app/ops_trace.py b/api/controllers/console/app/ops_trace.py
index 41acf39541..a1123a580e 100644
--- a/api/controllers/console/app/ops_trace.py
+++ b/api/controllers/console/app/ops_trace.py
@@ -128,6 +128,6 @@ class TraceAppConfigApi(Resource):
             result = OpsService.delete_tracing_app_config(app_id=app_model.id, tracing_provider=args.tracing_provider)
             if not result:
                 raise TracingConfigNotExist()
-            return {"result": "success"}, 204
+            return "", 204
         except Exception as e:
             raise BadRequest(str(e))
diff --git a/api/controllers/console/app/workflow_comment.py b/api/controllers/console/app/workflow_comment.py
index f011f576fd..27009953b7 100644
--- a/api/controllers/console/app/workflow_comment.py
+++ b/api/controllers/console/app/workflow_comment.py
@@ -311,7 +311,7 @@ class WorkflowCommentDetailApi(Resource):
             user_id=current_user.id,
         )
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/apps/<uuid:app_id>/workflow/comments/<string:comment_id>/resolve")
@@ -431,7 +431,7 @@ class WorkflowCommentReplyDetailApi(Resource):
             user_id=current_user.id,
         )
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/apps/<uuid:app_id>/workflow/comments/mention-users")
diff --git a/api/controllers/console/auth/data_source_bearer_auth.py b/api/controllers/console/auth/data_source_bearer_auth.py
index 2e3b8d2295..3f0650389f 100644
--- a/api/controllers/console/auth/data_source_bearer_auth.py
+++ b/api/controllers/console/auth/data_source_bearer_auth.py
@@ -93,4 +93,4 @@ class ApiKeyAuthDataSourceBindingDelete(Resource):
 
         ApiKeyAuthService.delete_provider_auth(current_tenant_id, binding_id)
 
-        return {"result": "success"}, 204
+        return "", 204
diff --git a/api/controllers/console/datasets/datasets.py b/api/controllers/console/datasets/datasets.py
index 0c5bf88a5a..e1666d92d1 100644
--- a/api/controllers/console/datasets/datasets.py
+++ b/api/controllers/console/datasets/datasets.py
@@ -535,7 +535,7 @@ class DatasetApi(Resource):
         try:
             if DatasetService.delete_dataset(dataset_id_str, current_user):
                 DatasetPermissionService.clear_partial_member_list(dataset_id_str)
-                return {"result": "success"}, 204
+                return "", 204
             else:
                 raise NotFound("Dataset not found.")
         except services.errors.dataset.DatasetInUseError:
@@ -873,7 +873,7 @@ class DatasetApiDeleteApi(Resource):
         db.session.delete(key)
         db.session.commit()
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/<uuid:dataset_id>/api-keys/<string:status>")
diff --git a/api/controllers/console/datasets/datasets_document.py b/api/controllers/console/datasets/datasets_document.py
index d98da48daa..fabd61e6b0 100644
--- a/api/controllers/console/datasets/datasets_document.py
+++ b/api/controllers/console/datasets/datasets_document.py
@@ -504,7 +504,7 @@ class DatasetDocumentListApi(Resource):
         except services.errors.document.DocumentIndexingError:
             raise DocumentIndexingError("Cannot delete document during indexing.")
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/init")
@@ -966,7 +966,7 @@ class DocumentApi(DocumentResource):
         except services.errors.document.DocumentIndexingError:
             raise DocumentIndexingError("Cannot delete document during indexing.")
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/<uuid:dataset_id>/documents/<uuid:document_id>/download")
@@ -1204,7 +1204,7 @@ class DocumentPauseApi(DocumentResource):
         except services.errors.document.DocumentIndexingError:
             raise DocumentIndexingError("Cannot pause completed document.")
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/<uuid:dataset_id>/documents/<uuid:document_id>/processing/resume")
@@ -1236,7 +1236,7 @@ class DocumentRecoverApi(DocumentResource):
         except services.errors.document.DocumentIndexingError:
             raise DocumentIndexingError("Document is not in paused status.")
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/<uuid:dataset_id>/retry")
@@ -1279,7 +1279,7 @@ class DocumentRetryApi(DocumentResource):
         # retry document
         DocumentService.retry_document(dataset_id, retry_documents)
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/<uuid:dataset_id>/documents/<uuid:document_id>/rename")
diff --git a/api/controllers/console/datasets/datasets_segments.py b/api/controllers/console/datasets/datasets_segments.py
index 2eaa64994e..1d3bc96c1b 100644
--- a/api/controllers/console/datasets/datasets_segments.py
+++ b/api/controllers/console/datasets/datasets_segments.py
@@ -251,7 +251,7 @@ class DatasetDocumentSegmentListApi(Resource):
         except services.errors.account.NoPermissionError as e:
             raise Forbidden(str(e))
         SegmentService.delete_segments(segment_ids, document, dataset)
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/<uuid:dataset_id>/documents/<uuid:document_id>/segment/<string:action>")
@@ -467,7 +467,7 @@ class DatasetDocumentSegmentUpdateApi(Resource):
         except services.errors.account.NoPermissionError as e:
             raise Forbidden(str(e))
         SegmentService.delete_segment(segment, document, dataset)
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route(
@@ -754,7 +754,7 @@ class ChildChunkUpdateApi(Resource):
             SegmentService.delete_child_chunk(child_chunk, dataset)
         except ChildChunkDeleteIndexServiceError as e:
             raise ChildChunkDeleteIndexError(str(e))
-        return {"result": "success"}, 204
+        return "", 204
 
     @setup_required
     @login_required
diff --git a/api/controllers/console/datasets/external.py b/api/controllers/console/datasets/external.py
index 37cee1c17a..d1cdc15d0b 100644
--- a/api/controllers/console/datasets/external.py
+++ b/api/controllers/console/datasets/external.py
@@ -218,7 +218,7 @@ class ExternalApiTemplateApi(Resource):
             raise Forbidden()
 
         ExternalDatasetService.delete_external_knowledge_api(current_tenant_id, external_knowledge_api_id)
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/datasets/external-knowledge-api/<uuid:external_knowledge_api_id>/use-check")
diff --git a/api/controllers/console/explore/conversation.py b/api/controllers/console/explore/conversation.py
index 826610acda..ae32571219 100644
--- a/api/controllers/console/explore/conversation.py
+++ b/api/controllers/console/explore/conversation.py
@@ -105,7 +105,7 @@ class ConversationApi(InstalledAppResource):
         except ConversationNotExistsError:
             raise NotFound("Conversation Not Exists.")
 
-        return ResultResponse(result="success").model_dump(mode="json"), 204
+        return "", 204
 
 
 @console_ns.route(
diff --git a/api/controllers/console/explore/installed_app.py b/api/controllers/console/explore/installed_app.py
index fb8d35013f..4ad3dbc85f 100644
--- a/api/controllers/console/explore/installed_app.py
+++ b/api/controllers/console/explore/installed_app.py
@@ -270,7 +270,7 @@ class InstalledAppApi(InstalledAppResource):
         db.session.delete(installed_app)
         db.session.commit()
 
-        return {"result": "success", "message": "App uninstalled successfully"}, 204
+        return "", 204
 
     @console_ns.response(200, "Success", console_ns.models[SimpleResultMessageResponse.__name__])
     def patch(self, installed_app):
diff --git a/api/controllers/console/explore/saved_message.py b/api/controllers/console/explore/saved_message.py
index 51e73049a4..09f214bd2b 100644
--- a/api/controllers/console/explore/saved_message.py
+++ b/api/controllers/console/explore/saved_message.py
@@ -76,4 +76,4 @@ class SavedMessageApi(InstalledAppResource):
 
         SavedMessageService.delete(app_model, current_user, message_id)
 
-        return ResultResponse(result="success").model_dump(mode="json"), 204
+        return "", 204
diff --git a/api/controllers/console/extension.py b/api/controllers/console/extension.py
index e53bb95c24..35e62e3c7e 100644
--- a/api/controllers/console/extension.py
+++ b/api/controllers/console/extension.py
@@ -204,4 +204,4 @@ class APIBasedExtensionDetailAPI(Resource):
 
         APIBasedExtensionService.delete(extension_data_from_db)
 
-        return {"result": "success"}, 204
+        return "", 204
diff --git a/api/controllers/console/workspace/model_providers.py b/api/controllers/console/workspace/model_providers.py
index f00a7e5c79..221cb3e406 100644
--- a/api/controllers/console/workspace/model_providers.py
+++ b/api/controllers/console/workspace/model_providers.py
@@ -194,7 +194,7 @@ class ModelProviderCredentialApi(Resource):
             tenant_id=current_tenant_id, provider=provider, credential_id=args.credential_id
         )
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/workspaces/current/model-providers/<path:provider>/credentials/switch")
diff --git a/api/controllers/console/workspace/models.py b/api/controllers/console/workspace/models.py
index a24d6d0f7d..c23207e402 100644
--- a/api/controllers/console/workspace/models.py
+++ b/api/controllers/console/workspace/models.py
@@ -259,7 +259,7 @@ class ModelProviderModelApi(Resource):
             tenant_id=tenant_id, provider=provider, model=args.model, model_type=args.model_type
         )
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/workspaces/current/model-providers/<path:provider>/models/credentials")
@@ -395,7 +395,7 @@ class ModelProviderModelCredentialApi(Resource):
             credential_id=args.credential_id,
         )
 
-        return {"result": "success"}, 204
+        return "", 204
 
 
 @console_ns.route("/workspaces/current/model-providers/<path:provider>/models/credentials/switch")
diff --git a/api/controllers/web/conversation.py b/api/controllers/web/conversation.py
index 6afa00c727..a99adb391f 100644
--- a/api/controllers/web/conversation.py
+++ b/api/controllers/web/conversation.py
@@ -136,7 +136,7 @@ class ConversationApi(WebApiResource):
             ConversationService.delete(app_model, conversation_id, end_user)
         except ConversationNotExistsError:
             raise NotFound("Conversation Not Exists.")
-        return ResultResponse(result="success").model_dump(mode="json"), 204
+        return "", 204
 
 
 @web_ns.route("/conversations/<uuid:c_id>/name")
diff --git a/api/controllers/web/saved_message.py b/api/controllers/web/saved_message.py
index b1382efbd8..e307367b64 100644
--- a/api/controllers/web/saved_message.py
+++ b/api/controllers/web/saved_message.py
@@ -112,4 +112,4 @@ class SavedMessageApi(WebApiResource):
 
         SavedMessageService.delete(app_model, end_user, message_id)
 
-        return ResultResponse(result="success").model_dump(mode="json"), 204
+        return "", 204
diff --git a/api/tests/test_containers_integration_tests/controllers/console/explore/test_conversation.py b/api/tests/test_containers_integration_tests/controllers/console/explore/test_conversation.py
index 917aa35fe6..b5f5917ee9 100644
--- a/api/tests/test_containers_integration_tests/controllers/console/explore/test_conversation.py
+++ b/api/tests/test_containers_integration_tests/controllers/console/explore/test_conversation.py
@@ -128,7 +128,7 @@ class TestConversationApi:
 
         body, status = result
         assert status == 204
-        assert body["result"] == "success"
+        assert body == ""
 
     def test_delete_not_found(self, app: Flask, chat_app, user):
         api = conversation_module.ConversationApi()
diff --git a/api/tests/test_containers_integration_tests/controllers/web/test_conversation.py b/api/tests/test_containers_integration_tests/controllers/web/test_conversation.py
index c34da27ebe..0ec399ba2b 100644
--- a/api/tests/test_containers_integration_tests/controllers/web/test_conversation.py
+++ b/api/tests/test_containers_integration_tests/controllers/web/test_conversation.py
@@ -81,7 +81,7 @@ class TestConversationApi:
             result, status = ConversationApi().delete(_chat_app(), _end_user(), c_id)
 
         assert status == 204
-        assert result["result"] == "success"
+        assert result == ""
 
     @patch("controllers.web.conversation.ConversationService.delete", side_effect=ConversationNotExistsError())
     def test_delete_not_found(self, mock_delete: MagicMock, app: Flask) -> None:
diff --git a/api/tests/unit_tests/controllers/console/datasets/test_datasets.py b/api/tests/unit_tests/controllers/console/datasets/test_datasets.py
index e28d68ee5a..4b0dff037f 100644
--- a/api/tests/unit_tests/controllers/console/datasets/test_datasets.py
+++ b/api/tests/unit_tests/controllers/console/datasets/test_datasets.py
@@ -873,7 +873,7 @@ class TestDatasetApiDelete:
             result, status = method(api, dataset_id)
 
         assert status == 204
-        assert result == {"result": "success"}
+        assert result == ""
 
     def test_delete_forbidden_no_permission(self, app: Flask):
         api = DatasetApi()
@@ -1687,7 +1687,7 @@ class TestDatasetApiDeleteApi:
             response, status = method(api, "api-key-id")
 
         assert status == 204
-        assert response["result"] == "success"
+        assert response == ""
 
     def test_delete_key_not_found(self, app: Flask):
         api = DatasetApiDeleteApi()
diff --git a/api/tests/unit_tests/controllers/console/datasets/test_datasets_segments.py b/api/tests/unit_tests/controllers/console/datasets/test_datasets_segments.py
index 66d257ee66..eb99c4eab3 100644
--- a/api/tests/unit_tests/controllers/console/datasets/test_datasets_segments.py
+++ b/api/tests/unit_tests/controllers/console/datasets/test_datasets_segments.py
@@ -940,7 +940,7 @@ class TestChildChunkUpdateApi:
             response, status = method(api, "ds-1", "doc-1", "seg-1", "cc-1")
 
         assert status == 204
-        assert response["result"] == "success"
+        assert response == ""
 
     def test_delete_child_chunk_index_error(self, app: Flask):
         api = ChildChunkUpdateApi()
diff --git a/api/tests/unit_tests/controllers/console/explore/test_installed_app.py b/api/tests/unit_tests/controllers/console/explore/test_installed_app.py
index ec82803be4..47ac8d8f3f 100644
--- a/api/tests/unit_tests/controllers/console/explore/test_installed_app.py
+++ b/api/tests/unit_tests/controllers/console/explore/test_installed_app.py
@@ -327,7 +327,7 @@ class TestInstalledAppApi:
             resp, status = method(installed_app)
 
         assert status == 204
-        assert resp["result"] == "success"
+        assert resp == ""
 
     def test_delete_owned_by_current_tenant(self, tenant_id: str):
         api = module.InstalledAppApi()
diff --git a/api/tests/unit_tests/controllers/console/explore/test_saved_message.py b/api/tests/unit_tests/controllers/console/explore/test_saved_message.py
index 49e5695e60..00c0d91d1d 100644
--- a/api/tests/unit_tests/controllers/console/explore/test_saved_message.py
+++ b/api/tests/unit_tests/controllers/console/explore/test_saved_message.py
@@ -141,7 +141,7 @@ class TestSavedMessageApi:
 
         delete_mock.assert_called_once()
         assert status == 204
-        assert result == {"result": "success"}
+        assert result == ""
 
     def test_delete_not_completion_app(self):
         api = module.SavedMessageApi()
diff --git a/api/tests/unit_tests/controllers/console/test_extension.py b/api/tests/unit_tests/controllers/console/test_extension.py
index 2a33ee12be..20fc62073b 100644
--- a/api/tests/unit_tests/controllers/console/test_extension.py
+++ b/api/tests/unit_tests/controllers/console/test_extension.py
@@ -242,5 +242,5 @@ def test_api_based_extension_detail_delete_removes_extension(app: Flask, monkeyp
         response, status = APIBasedExtensionDetailAPI().delete(extension_id)
 
     delete_mock.assert_called_once_with(existing_extension)
-    assert response == {"result": "success"}
     assert status == 204
+    assert response == ""
diff --git a/api/tests/unit_tests/controllers/console/workspace/test_model_providers.py b/api/tests/unit_tests/controllers/console/workspace/test_model_providers.py
index e836a3cc55..a81a8e1b1a 100644
--- a/api/tests/unit_tests/controllers/console/workspace/test_model_providers.py
+++ b/api/tests/unit_tests/controllers/console/workspace/test_model_providers.py
@@ -179,8 +179,8 @@ class TestModelProviderCredentialApi:
         ):
             result, status = method(api, provider="openai")
 
-        assert result["result"] == "success"
         assert status == 204
+        assert result == ""
 
 
 class TestModelProviderCredentialSwitchApi:
diff --git a/api/tests/unit_tests/controllers/web/test_saved_message.py b/api/tests/unit_tests/controllers/web/test_saved_message.py
index 3d55804912..5de740192f 100644
--- a/api/tests/unit_tests/controllers/web/test_saved_message.py
+++ b/api/tests/unit_tests/controllers/web/test_saved_message.py
@@ -94,4 +94,4 @@ class TestSavedMessageApi:
             result, status = SavedMessageApi().delete(_completion_app(), _end_user(), msg_id)
 
         assert status == 204
-        assert result["result"] == "success"
+        assert result == ""