diff --git a/apps/backend/chatballs/ai/invocation.py b/apps/backend/chatballs/ai/invocation.py
index f1e443c..cb9fa37 100644
--- a/apps/backend/chatballs/ai/invocation.py
+++ b/apps/backend/chatballs/ai/invocation.py
@@ -31,6 +31,7 @@ from chatballs.ai.provider.base import (
 from chatballs.ai.provider.factory import get_provider
 from chatballs.ai.provider.resilience import CircuitBreaker, call_with_resilience
 
+
 # Предохранитель считает сбои по ключу «организация + интеграция»: провайдер у
 # каждой организации свой, и отозванный ключ одной не имеет отношения к AI
 # остальных. Общий на процесс предохранитель гасил AI у всех сразу.
diff --git a/apps/backend/chatballs/ai/provider/openai_http.py b/apps/backend/chatballs/ai/provider/openai_http.py
index 77d4a4a..a318bc6 100644
--- a/apps/backend/chatballs/ai/provider/openai_http.py
+++ b/apps/backend/chatballs/ai/provider/openai_http.py
@@ -38,17 +38,11 @@ import urllib.error
 import urllib.request
 
 from chatballs.ai.provider.base import (
-
     ChatMessage,
-
     ChatResult,
-
     EmbeddingResult,
-
     ProviderError,
-
     ProviderRejected,
-
 )
 from chatballs.i18n import t
 from chatballs.integrations.proxy import build_opener
diff --git a/apps/backend/chatballs/conversations/apps.py b/apps/backend/chatballs/conversations/apps.py
index a6d0b6f..fe136b3 100644
--- a/apps/backend/chatballs/conversations/apps.py
+++ b/apps/backend/chatballs/conversations/apps.py
@@ -9,5 +9,7 @@ class ConversationsConfig(AppConfig):
 
     def ready(self) -> None:
         # Свежесть диалога поддерживает сигнал: сообщения создаются в семи местах.
-        from chatballs.conversations import signals  # noqa: F401
-        from chatballs.conversations import event_handlers  # noqa: F401  (register outbox handlers)
+        from chatballs.conversations import (
+            event_handlers,  # noqa: F401  (register outbox handlers)
+            signals,  # noqa: F401
+        )
diff --git a/apps/backend/chatballs/conversations/test_email_transport.py b/apps/backend/chatballs/conversations/test_email_transport.py
index f7368ee..5da6b95 100644
--- a/apps/backend/chatballs/conversations/test_email_transport.py
+++ b/apps/backend/chatballs/conversations/test_email_transport.py
@@ -19,7 +19,6 @@ from chatballs.conversations.transports.errors import PollFailed
 from chatballs.identity.bootstrap import bootstrap_owner
 from chatballs.identity.models import Organization
 from chatballs.integrations.models import Integration, IntegrationKind, IntegrationProvider
-
 from chatballs.testing import ai_answer, run_pending_ai_turns
 
 EMAIL_CONFIG = {
diff --git a/apps/backend/chatballs/conversations/test_lifecycle.py b/apps/backend/chatballs/conversations/test_lifecycle.py
index d6db42f..1399b89 100644
--- a/apps/backend/chatballs/conversations/test_lifecycle.py
+++ b/apps/backend/chatballs/conversations/test_lifecycle.py
@@ -22,7 +22,8 @@ from chatballs.integrations.models import (
     IntegrationKind,
     IntegrationProvider,
 )
-from chatballs.testing import TenantAPIClient as APIClient, run_pending_ai_turns
+from chatballs.testing import TenantAPIClient as APIClient
+from chatballs.testing import run_pending_ai_turns
 
 
 def _connection(channel: Channel) -> Integration:
diff --git a/apps/backend/chatballs/conversations/test_voice_ai_and_features.py b/apps/backend/chatballs/conversations/test_voice_ai_and_features.py
index 8fd3119..4d4811d 100644
--- a/apps/backend/chatballs/conversations/test_voice_ai_and_features.py
+++ b/apps/backend/chatballs/conversations/test_voice_ai_and_features.py
@@ -9,6 +9,7 @@ from django.test import TestCase
 from chatballs.ai.models import AIAgent, AIAgentStatus
 from chatballs.ai.provider.base import ProviderError
 from chatballs.channels.models import Channel
+from chatballs.conversations import ai_turn
 from chatballs.conversations.ingest import ingest_inbound
 from chatballs.conversations.models import ControlMode, MessageAuthor, MessageKind, TranscriptStatus
 from chatballs.conversations.transports.base import InboundMessage
@@ -16,8 +17,8 @@ from chatballs.identity.bootstrap import bootstrap_owner
 from chatballs.identity.models import Organization
 from chatballs.integrations.models import Integration, IntegrationKind, IntegrationProvider
 from chatballs.tenancy.database import tenant_atomic
-from chatballs.conversations import ai_turn
-from chatballs.testing import TenantAPIClient as APIClient, ai_answer, run_pending_ai_turns
+from chatballs.testing import TenantAPIClient as APIClient
+from chatballs.testing import ai_answer, run_pending_ai_turns
 
 
 class VoiceAiReplyTests(TestCase):
diff --git a/apps/backend/chatballs/conversations/tests.py b/apps/backend/chatballs/conversations/tests.py
index d888f97..dfc339d 100644
--- a/apps/backend/chatballs/conversations/tests.py
+++ b/apps/backend/chatballs/conversations/tests.py
@@ -27,8 +27,8 @@ from chatballs.identity.models import (
 )
 from chatballs.integrations.models import Integration, IntegrationKind, IntegrationProvider
 from chatballs.notifications.models import Notification, NotificationAudience, NotificationType
-from chatballs.testing import ai_answer, ai_failure, run_pending_ai_turns
 from chatballs.testing import TenantAPIClient as APIClient
+from chatballs.testing import ai_answer, ai_failure, run_pending_ai_turns
 
 
 def _messenger_connection(channel):
diff --git a/apps/backend/chatballs/events/services.py b/apps/backend/chatballs/events/services.py
index c643801..9b1f025 100644
--- a/apps/backend/chatballs/events/services.py
+++ b/apps/backend/chatballs/events/services.py
@@ -12,7 +12,6 @@ from chatballs.identity.models import OrganizationMembership
 from chatballs.tenancy.context import TenantActorKind, TenantContext
 from chatballs.tenancy.lookup import load_organization
 
-
 # Где живёт outbox. Захват идёт по всем организациям сразу, поэтому читает и
 # отмечает события роль platform, а не app (chatballs.tenancy.routing).
 OUTBOX_DB = "platform"
diff --git a/apps/backend/chatballs/integrations/checking.py b/apps/backend/chatballs/integrations/checking.py
index d94acf0..d97dbc1 100644
--- a/apps/backend/chatballs/integrations/checking.py
+++ b/apps/backend/chatballs/integrations/checking.py
@@ -7,7 +7,6 @@ from chatballs.integrations.models import Integration, IntegrationProvider, Inte
 from chatballs.integrations.runtime import advance_revision_after_successful_check
 from chatballs.tenancy.context import TenantContext
 
-
 _CHECKS = {
     IntegrationProvider.OPENROUTER: checks.check_openrouter,
     IntegrationProvider.CUSTOM: checks.check_custom,