diff --git a/config/config.yaml b/config/config.yaml
index fc6961f9e..bed67083c 100644
--- a/config/config.yaml
+++ b/config/config.yaml
@@ -7,7 +7,7 @@
 ## Or, you can configure OPENAI_PROXY to access official OPENAI_API_BASE.
 OPENAI_API_BASE: "https://api.openai.com/v1"
 #OPENAI_PROXY: "http://127.0.0.1:8118"
-#OPENAI_API_KEY: "YOUR_API_KEY"
+#OPENAI_API_KEY: "YOUR_API_KEY"   # set the value to sk-xxx if you host the openai interface for open llm model
 OPENAI_API_MODEL: "gpt-4"
 MAX_TOKENS: 1500
 RPM: 10
@@ -32,7 +32,7 @@ RPM: 10
 #DEPLOYMENT_ID: "YOUR_DEPLOYMENT_ID"
 
 #### if zhipuai from `https://open.bigmodel.cn`. You can set here or export API_KEY="YOUR_API_KEY"
-ZHIPUAI_API_KEY: "YOUR_API_KEY"
+# ZHIPUAI_API_KEY: "YOUR_API_KEY"
 
 #### for Search
 
diff --git a/metagpt/llm.py b/metagpt/llm.py
index e9b80d7a8..13e5a56e0 100644
--- a/metagpt/llm.py
+++ b/metagpt/llm.py
@@ -17,13 +17,15 @@ from metagpt.provider.spark_api import SparkAPI
 def LLM() -> "BaseGPTAPI":
     """ initialize different LLM instance according to the key field existence"""
     # TODO a little trick, can use registry to initialize LLM instance further
-    if CONFIG.openai_api_key and CONFIG.openai_api_key.starswith("sk-"):
+    if CONFIG.openai_api_key and CONFIG.openai_api_key.startswith("sk-"):
         llm = OpenAIGPTAPI()
     elif CONFIG.claude_api_key:
         llm = Claude()
     elif CONFIG.spark_api_key:
         llm = SparkAPI()
-    elif CONFIG.zhipuai_api_key:
+    elif CONFIG.zhipuai_api_key and CONFIG.zhipuai_api_key != "YOUR_API_KEY":
         llm = ZhiPuAIGPTAPI()
+    else:
+        raise RuntimeError("You should config a LLM configuration first")
 
     return llm