diff --git a/modified_assistant.py b/modified_assistant.py
index d9a9843..6cfac51 100644
--- a/modified_assistant.py
+++ b/modified_assistant.py
@@ -177,7 +177,24 @@ class ModifiedAssistant(Assistant):
                 # 如果使用了工具，继续循环
                 if not used_any_tool:
                     break
-                    
+
+        # 检查是否因为调用次数用完而退出循环
+        if num_llm_calls_available == 0:
+            # 根据语言选择错误消息
+            if lang == 'zh':
+                error_message = "工具调用超出限制"
+            elif lang == 'ja':
+                error_message = "ツール呼び出しが制限を超えました。"
+            else:
+                error_message = "Tool calls exceeded limit"
+            tool_logger.error(error_message)
+
+            error_msg = Message(
+                role=ASSISTANT,
+                content=error_message,
+            )
+            response.append(error_msg)
+
         yield response
 
 
diff --git a/utils/fastapi_utils.py b/utils/fastapi_utils.py
index 69064f7..6aabcd9 100644
--- a/utils/fastapi_utils.py
+++ b/utils/fastapi_utils.py
@@ -284,6 +284,10 @@ def extract_guidelines_from_system_prompt(system_prompt: Optional[str]) -> tuple
     pattern = r'```guideline\s*\n(.*?)\n```'
     matches = re.findall(pattern, system_prompt, re.DOTALL)
 
+    # 如果没有匹配到guidelines，直接返回空字符串和原始prompt
+    if not matches:
+        return system_prompt, ""
+
     guidelines_text = "\n".join(matches).strip()
 
     # 从原始system_prompt中删除 ```guideline``` 内容块