diff --git a/backend/knowledge_reasoner.py b/backend/knowledge_reasoner.py
index 1a84dea..b1d8d10 100644
--- a/backend/knowledge_reasoner.py
+++ b/backend/knowledge_reasoner.py
@@ -124,7 +124,7 @@ class KnowledgeReasoner:
         if json_match:
             try:
                 return json.loads(json_match.group())
-            except BaseException:
+            except (json.JSONDecodeError, KeyError):
                 pass
 
         return {"type": "factual", "entities": [], "intent": "general", "complexity": "simple"}
@@ -178,7 +178,7 @@ class KnowledgeReasoner:
                     related_entities=[],
                     gaps=data.get("knowledge_gaps", []),
                 )
-            except BaseException:
+            except (json.JSONDecodeError, KeyError):
                 pass
 
         return ReasoningResult(
@@ -232,7 +232,7 @@ class KnowledgeReasoner:
                     related_entities=[],
                     gaps=data.get("knowledge_gaps", []),
                 )
-            except BaseException:
+            except (json.JSONDecodeError, KeyError):
                 pass
 
         return ReasoningResult(
@@ -286,7 +286,7 @@ class KnowledgeReasoner:
                     related_entities=[],
                     gaps=data.get("knowledge_gaps", []),
                 )
-            except BaseException:
+            except (json.JSONDecodeError, KeyError):
                 pass
 
         return ReasoningResult(
@@ -340,7 +340,7 @@ class KnowledgeReasoner:
                     related_entities=[],
                     gaps=data.get("knowledge_gaps", []),
                 )
-            except BaseException:
+            except (json.JSONDecodeError, KeyError):
                 pass
 
         return ReasoningResult(
@@ -360,8 +360,6 @@ class KnowledgeReasoner:
 
         使用 BFS 在关系图中搜索路径
         """
-        # 实体数据可用于调试或扩展功能
-        _ = {e["id"]: e for e in graph_data.get("entities", [])}
         relations = graph_data.get("relations", [])
 
         # 构建邻接表
@@ -483,7 +481,7 @@ class KnowledgeReasoner:
         if json_match:
             try:
                 return json.loads(json_match.group())
-            except BaseException:
+            except (json.JSONDecodeError, KeyError):
                 pass
 
         return {
diff --git a/backend/search_manager.py b/backend/search_manager.py
index e0331fc..f92564c 100644
--- a/backend/search_manager.py
+++ b/backend/search_manager.py
@@ -36,7 +36,6 @@ try:
 except ImportError:
     SENTENCE_TRANSFORMERS_AVAILABLE = False
 
-
 # ==================== 数据模型 ====================
 
 @dataclass
diff --git a/backend/test_multimodal.py b/backend/test_multimodal.py
index d009ab6..a5af2ff 100644
--- a/backend/test_multimodal.py
+++ b/backend/test_multimodal.py
@@ -46,7 +46,7 @@ print("\n2. 测试模块初始化...")
 
 try:
     processor = get_multimodal_processor()
-    print(f"   ✓ MultimodalProcessor 初始化成功")
+    print("   ✓ MultimodalProcessor 初始化成功")
     print(f"     - 临时目录: {processor.temp_dir}")
     print(f"     - 帧提取间隔: {processor.frame_interval}秒")
 except Exception as e:
@@ -54,14 +54,14 @@ except Exception as e:
 
 try:
     img_processor = get_image_processor()
-    print(f"   ✓ ImageProcessor 初始化成功")
+    print("   ✓ ImageProcessor 初始化成功")
     print(f"     - 临时目录: {img_processor.temp_dir}")
 except Exception as e:
     print(f"   ✗ ImageProcessor 初始化失败: {e}")
 
 try:
     linker = get_multimodal_entity_linker()
-    print(f"   ✓ MultimodalEntityLinker 初始化成功")
+    print("   ✓ MultimodalEntityLinker 初始化成功")
     print(f"     - 相似度阈值: {linker.similarity_threshold}")
 except Exception as e:
     print(f"   ✗ MultimodalEntityLinker 初始化失败: {e}")
diff --git a/backend/test_phase7_task6_8.py b/backend/test_phase7_task6_8.py
index 418eed0..7cddc03 100644
--- a/backend/test_phase7_task6_8.py
+++ b/backend/test_phase7_task6_8.py
@@ -157,8 +157,8 @@ def test_cache_manager():
     print("   ✓ 设置缓存 test_key_1")
 
     # 获取缓存
-    value = cache.get("test_key_1")
-    print(f"   ✓ 获取缓存: {value}")
+    _ = cache.get("test_key_1")
+    print("   ✓ 获取缓存: {value}")
 
     # 批量操作
     cache.set_many({
@@ -168,8 +168,8 @@ def test_cache_manager():
     }, ttl=60)
     print("   ✓ 批量设置缓存")
 
-    values = cache.get_many(["batch_key_1", "batch_key_2", "batch_key_3"])
-    print(f"   ✓ 批量获取缓存: {len(values)} 个")
+    _ = cache.get_many(["batch_key_1", "batch_key_2", "batch_key_3"])
+    print("   ✓ 批量获取缓存: {len(values)} 个")
 
     # 删除缓存
     cache.delete("test_key_1")
@@ -177,7 +177,7 @@ def test_cache_manager():
 
     # 获取统计
     stats = cache.get_stats()
-    print(f"\n3. 缓存统计:")
+    print("\n3. 缓存统计:")
     print(f"   总请求数: {stats['total_requests']}")
     print(f"   命中数: {stats['hits']}")
     print(f"   未命中数: {stats['misses']}")
@@ -216,16 +216,16 @@ def test_task_queue():
         task_type="test_task",
         payload={"test": "data", "timestamp": time.time()}
     )
-    print(f"   ✓ 提交任务: {task_id}")
+    print("   ✓ 提交任务: {task_id}")
 
     # 获取任务状态
     task_info = queue.get_status(task_id)
     if task_info:
-        print(f"   ✓ 任务状态: {task_info.status}")
+        print("   ✓ 任务状态: {task_info.status}")
 
     # 获取统计
     stats = queue.get_stats()
-    print(f"\n3. 任务队列统计:")
+    print("\n3. 任务队列统计:")
     print(f"   后端: {stats['backend']}")
     print(f"   按状态统计: {stats.get('by_status', {})}")
 
@@ -287,7 +287,7 @@ def test_search_manager():
     manager = get_search_manager()
 
     print("\n1. 搜索管理器初始化...")
-    print(f"   ✓ 搜索管理器已初始化")
+    print("   ✓ 搜索管理器已初始化")
 
     print("\n2. 获取搜索统计...")
     stats = manager.get_search_stats()
@@ -308,7 +308,7 @@ def test_performance_manager():
     manager = get_performance_manager()
 
     print("\n1. 性能管理器初始化...")
-    print(f"   ✓ 性能管理器已初始化")
+    print("   ✓ 性能管理器已初始化")
 
     print("\n2. 获取系统健康状态...")
     health = manager.get_health_status()
diff --git a/backend/test_phase8_task1.py b/backend/test_phase8_task1.py
index 1a745b4..0c33bf0 100644
--- a/backend/test_phase8_task1.py
+++ b/backend/test_phase8_task1.py
@@ -94,7 +94,7 @@ def test_domain_management(tenant_id: str):
     # 2. 获取验证指导
     print("\n2.2 获取域名验证指导...")
     instructions = manager.get_domain_verification_instructions(domain.id)
-    print(f"✅ 验证指导:")
+    print("✅ 验证指导:")
     print(f"   - DNS 记录: {instructions['dns_record']}")
     print(f"   - 文件验证: {instructions['file_verification']}")
 
@@ -141,7 +141,7 @@ def test_branding_management(tenant_id: str):
         custom_js="console.log('Custom JS loaded');",
         login_page_bg="https://example.com/bg.jpg"
     )
-    print(f"✅ 品牌配置更新成功")
+    print("✅ 品牌配置更新成功")
     print(f"   - Logo: {branding.logo_url}")
     print(f"   - 主色: {branding.primary_color}")
     print(f"   - 次色: {branding.secondary_color}")
@@ -150,7 +150,7 @@ def test_branding_management(tenant_id: str):
     print("\n3.2 获取品牌配置...")
     fetched = manager.get_branding(tenant_id)
     assert fetched is not None, "获取品牌配置失败"
-    print(f"✅ 获取品牌配置成功")
+    print("✅ 获取品牌配置成功")
 
     # 3. 生成品牌 CSS
     print("\n3.3 生成品牌 CSS...")
@@ -246,7 +246,7 @@ def test_usage_tracking(tenant_id: str):
     # 2. 获取使用统计
     print("\n5.2 获取使用统计...")
     stats = manager.get_usage_stats(tenant_id)
-    print(f"✅ 使用统计:")
+    print("✅ 使用统计:")
     print(f"   - 存储: {stats['storage_mb']:.2f} MB")
     print(f"   - 转录: {stats['transcription_minutes']:.2f} 分钟")
     print(f"   - API 调用: {stats['api_calls']}")
diff --git a/backend/test_phase8_task2.py b/backend/test_phase8_task2.py
index b090af4..95b353b 100644
--- a/backend/test_phase8_task2.py
+++ b/backend/test_phase8_task2.py
@@ -96,7 +96,7 @@ def test_subscription_manager():
 
         # 获取用量汇总
         summary = manager.get_usage_summary(tenant_id)
-        print(f"✓ 用量汇总:")
+        print("✓ 用量汇总:")
         print(f"  - 总费用: ¥{summary['total_cost']:.2f}")
         for resource, data in summary['breakdown'].items():
             print(f"  - {resource}: {data['quantity']} (¥{data['cost']:.2f})")
diff --git a/backend/test_phase8_task6.py b/backend/test_phase8_task6.py
index 29f6b3f..4b025cd 100644
--- a/backend/test_phase8_task6.py
+++ b/backend/test_phase8_task6.py
@@ -649,7 +649,7 @@ console.log('Upload complete:', result.id);
         try:
             if self.created_ids['developer']:
                 summary = self.manager.get_developer_revenue_summary(self.created_ids['developer'][0])
-                self.log(f"Revenue summary for developer:")
+                self.log("Revenue summary for developer:")
                 self.log(f"  - Total sales: {summary['total_sales']}")
                 self.log(f"  - Total fees: {summary['total_fees']}")
                 self.log(f"  - Total earnings: {summary['total_earnings']}")
diff --git a/backend/test_phase8_task8.py b/backend/test_phase8_task8.py
index 323ba7b..1237bee 100644
--- a/backend/test_phase8_task8.py
+++ b/backend/test_phase8_task8.py
@@ -521,7 +521,7 @@ class TestOpsManager:
                 self.manager.update_failover_status(event.id, "completed")
                 updated_event = self.manager.get_failover_event(event.id)
                 assert updated_event.status == "completed"
-                self.log(f"Failover completed")
+                self.log("Failover completed")
 
             # 获取故障转移事件列表
             events = self.manager.list_failover_events(self.tenant_id)
diff --git a/backend/tingwu_client.py b/backend/tingwu_client.py
index 72b8fab..44c4b91 100644
--- a/backend/tingwu_client.py
+++ b/backend/tingwu_client.py
@@ -34,24 +34,6 @@ class TingwuClient:
 
     def create_task(self, audio_url: str, language: str = "zh") -> str:
         """创建听悟任务"""
-        endpoint = f"{self.endpoint}/openapi/tingwu/v2/tasks"
-
-        payload = {
-            "Input": {
-                "Source": "OSS",
-                "FileUrl": audio_url
-            },
-            "Parameters": {
-                "Transcription": {
-                    "DiarizationEnabled": True,
-                    "SentenceMaxLength": 20
-                }
-            }
-        }
-
-        # 使用阿里云 SDK 方式调用 (endpoint 和 payload 供后续扩展使用)
-        _ = endpoint
-        _ = payload
         try:
             from alibabacloud_tingwu20230930 import models as tingwu_models
             from alibabacloud_tingwu20230930.client import Client as TingwuSDKClient
diff --git a/backend/workflow_manager.py b/backend/workflow_manager.py
index e922709..a1ba454 100644
--- a/backend/workflow_manager.py
+++ b/backend/workflow_manager.py
@@ -1128,9 +1128,6 @@ class WorkflowManager:
         results = {}
         completed_tasks = set()
 
-        # 构建任务映射 (保留供调试使用)
-        _ = {t.id: t for t in tasks}
-
         while len(completed_tasks) < len(tasks):
             # 找到可以执行的任务（依赖已完成）
             ready_tasks = [
@@ -1310,7 +1307,7 @@ class WorkflowManager:
         if webhook.template:
             try:
                 message = json.loads(webhook.template.format(**input_data))
-            except BaseException:
+            except (json.JSONDecodeError, KeyError, ValueError):
                 pass
 
         success = await self.notifier.send(webhook, message)