diff --git a/metagpt/provider/openai_api.py b/metagpt/provider/openai_api.py
index bbceac1d2..30b82b8dc 100644
--- a/metagpt/provider/openai_api.py
+++ b/metagpt/provider/openai_api.py
@@ -277,9 +277,9 @@ class OpenAIGPTAPI(BaseGPTAPI, RateLimiter):
 
     async def is_related(self, text1, text2):
         # command = f"{text1}\n{text2}\n\nIf the two sentences above are related, return [TRUE] brief and clear. Otherwise, return [FALSE]."
-        command = f"{text2}\n\nIs there any sentence above related to the following sentence: {text1}.\nIf is there any relevance, return [TRUE]:1 brief and clear. Otherwise, return [FALSE]:1 brief and clear."
+        command = f"{text2}\n\nIs there any sentence above related to the following sentence: {text1}.\nIf is there any relevance, return [TRUE] brief and clear. Otherwise, return [FALSE] brief and clear."
         rsp = await self.aask(msg=command, system_msgs=[])
-        result, _ = self.extract_info(rsp)
+        result, _ = self.extract_info(rsp, pattern=r"\[([A-Z]+)\]\s*(.+)")
         return result == "TRUE"
 
     async def rewrite(self, sentence: str, context: str):