diff --git a/src/web/app.py b/src/web/app.py
index 3040855..912ad57 100644
--- a/src/web/app.py
+++ b/src/web/app.py
@@ -373,12 +373,15 @@ def end_chat_session(session_id):
 def get_active_sessions():
     """获取活跃会话列表"""
     try:
-        sessions = chat_manager.get_active_sessions()
+        # 确保chat_manager已初始化
+        manager = get_chat_manager()
+        sessions = manager.get_active_sessions()
         return jsonify({
             "success": True,
             "sessions": sessions
         })
     except Exception as e:
+        logger.error(f"获取活跃会话失败: {e}")
         return jsonify({"error": str(e)}), 500
 
 # Agent相关API
@@ -592,9 +595,29 @@ def get_analytics():
         # 支持多种参数
         time_range = request.args.get('timeRange', request.args.get('days', '30'))
         dimension = request.args.get('dimension', 'workorders')
-        analytics = generate_db_analytics(int(time_range), dimension)
+        
+        # 参数验证
+        try:
+            days = int(time_range)
+            if days <= 0 or days > 365:
+                days = 30
+        except (ValueError, TypeError):
+            days = 30
+        
+        analytics = generate_db_analytics(days, dimension)
+        
+        # 确保返回的数据结构完整
+        if not analytics:
+            analytics = {
+                "workorders": {"total": 0, "open": 0, "resolved": 0, "trend": []},
+                "alerts": {"total": 0, "critical": 0, "warning": 0, "trend": []},
+                "conversations": {"total": 0, "avg_confidence": 0, "trend": []},
+                "performance": {"avg_response_time": 0, "success_rate": 0}
+            }
+        
         return jsonify(analytics)
     except Exception as e:
+        logger.error(f"获取分析数据失败: {e}")
         return jsonify({"error": str(e)}), 500
 
 def generate_db_analytics(days: int, dimension: str) -> dict: