diff --git a/backend/app/api/agent.py b/backend/app/api/agent.py
index 7cc356dc..f9cec9f5 100644
--- a/backend/app/api/agent.py
+++ b/backend/app/api/agent.py
@@ -155,8 +155,7 @@ def _agent_board_openapi_hints(
             "Authenticated agent token",
             "Board access is validated before execution",
         ],
-        "x-side-effects": side_effects
-        or ["Read/write side effects vary by endpoint semantics."],
+        "x-side-effects": side_effects or ["Read/write side effects vary by endpoint semantics."],
         "x-negative-guidance": negative_guidance
         or ["Avoid this endpoint when a focused sibling endpoint handles the action."],
         "x-routing-policy": routing_policy
@@ -525,7 +524,10 @@ async def list_tags(
             "description": "Caller is not board lead",
         },
         404: {"model": LLMErrorResponse, "description": "Assigned target agent does not exist"},
-        409: {"model": LLMErrorResponse, "description": "Dependency or assignment validation failed"},
+        409: {
+            "model": LLMErrorResponse,
+            "description": "Dependency or assignment validation failed",
+        },
         422: {"model": LLMErrorResponse, "description": "Payload validation failed"},
     },
     openapi_extra={
diff --git a/backend/app/api/board_group_memory.py b/backend/app/api/board_group_memory.py
index 3dfb3bc9..f59b5ff3 100644
--- a/backend/app/api/board_group_memory.py
+++ b/backend/app/api/board_group_memory.py
@@ -577,7 +577,9 @@ async def stream_board_group_memory_for_board(
                 "decision": "agent_board_group_memory_record",
             }
         ],
-        side_effects=["Persist new group-memory entries with optional agent notification dispatch."],
+        side_effects=[
+            "Persist new group-memory entries with optional agent notification dispatch."
+        ],
         routing_policy=[
             "Use for shared memory writes that should be visible across linked boards.",
             "Prefer direct board memory endpoints for board-local persistence.",
diff --git a/backend/app/main.py b/backend/app/main.py
index db33517f..0da66a6a 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -6,8 +6,8 @@ from contextlib import asynccontextmanager
 from typing import TYPE_CHECKING, Any
 
 from fastapi import APIRouter, FastAPI, status
-from fastapi.openapi.utils import get_openapi
 from fastapi.middleware.cors import CORSMiddleware
+from fastapi.openapi.utils import get_openapi
 from fastapi_pagination import add_pagination
 
 from app.api.activity import router as activity_router
@@ -397,7 +397,9 @@ def _inject_tagged_operation_openapi_docs(openapi_schema: dict[str, Any]) -> Non
                         continue
                     response_content = response.get("content")
                     if isinstance(response_content, dict):
-                        _inject_json_content_example(content=response_content, components=components)
+                        _inject_json_content_example(
+                            content=response_content, components=components
+                        )
 
 
 @asynccontextmanager
diff --git a/backend/app/schemas/agents.py b/backend/app/schemas/agents.py
index fbc05def..0e115d56 100644
--- a/backend/app/schemas/agents.py
+++ b/backend/app/schemas/agents.py
@@ -8,8 +8,8 @@ from typing import Any
 from uuid import UUID
 
 from pydantic import Field, field_validator
-from sqlmodel._compat import SQLModelConfig
 from sqlmodel import SQLModel
+from sqlmodel._compat import SQLModelConfig
 
 from app.schemas.common import NonEmptyStr
 
diff --git a/backend/app/schemas/errors.py b/backend/app/schemas/errors.py
index 0d4649fa..7eab0618 100644
--- a/backend/app/schemas/errors.py
+++ b/backend/app/schemas/errors.py
@@ -31,7 +31,10 @@ class LLMErrorResponse(SQLModel):
             "Error payload. Agents should rely on `code` when present and default "
             "to `message` for fallback display."
         ),
-        examples=["Invalid payload for lead escalation.", {"code": "not_found", "message": "Agent not found."}],
+        examples=[
+            "Invalid payload for lead escalation.",
+            {"code": "not_found", "message": "Agent not found."},
+        ],
     )
     request_id: str | None = Field(
         default=None,
diff --git a/backend/app/schemas/gateway_coordination.py b/backend/app/schemas/gateway_coordination.py
index fba74b60..a62a516d 100644
--- a/backend/app/schemas/gateway_coordination.py
+++ b/backend/app/schemas/gateway_coordination.py
@@ -6,8 +6,8 @@ from typing import Literal
 from uuid import UUID
 
 from pydantic import Field
-from sqlmodel._compat import SQLModelConfig
 from sqlmodel import SQLModel
+from sqlmodel._compat import SQLModelConfig
 
 from app.schemas.common import NonEmptyStr
 
diff --git a/backend/app/schemas/health.py b/backend/app/schemas/health.py
index 0e767605..e67d2d7b 100644
--- a/backend/app/schemas/health.py
+++ b/backend/app/schemas/health.py
@@ -13,4 +13,3 @@ class HealthStatusResponse(SQLModel):
         description="Indicates whether the probe check succeeded.",
         examples=[True],
     )
-