diff --git a/flaml/autogen/agentchat/conversable_agent.py b/flaml/autogen/agentchat/conversable_agent.py
index 813634119c..ec598edde0 100644
--- a/flaml/autogen/agentchat/conversable_agent.py
+++ b/flaml/autogen/agentchat/conversable_agent.py
@@ -611,6 +611,11 @@ def generate_code_execution_reply(
         if messages is None:
             messages = self._oai_messages[sender]
         last_n_messages = code_execution_config.pop("last_n_messages", 1)
+        
+        logs = ""
+        exitcode = 0
+        exitcode2str = "execution succeeded"
+        
         for i in range(min(len(messages), last_n_messages)):
             message = messages[-(i + 1)]
             code_blocks = extract_code(message["content"])
diff --git a/test/autogen/agentchat/test_conversable_agent.py b/test/autogen/agentchat/test_conversable_agent.py
index 23f4a223c2..521fcb6553 100644
--- a/test/autogen/agentchat/test_conversable_agent.py
+++ b/test/autogen/agentchat/test_conversable_agent.py
@@ -2,6 +2,17 @@
 from flaml.autogen.agentchat import ConversableAgent
 
 
+def test_generate_oai_reply_empty_messages():
+    agent = ConversableAgent(
+        "a0", max_consecutive_auto_reply=0,
+        llm_config=False, human_input_mode="NEVER"
+    )
+
+    _, output = agent.generate_code_execution_reply(messages=[], config={})
+
+    assert output == 'exitcode: 0 (execution succeeded)\nCode output: '
+
+
 def test_trigger():
     agent = ConversableAgent("a0", max_consecutive_auto_reply=0, llm_config=False, human_input_mode="NEVER")
     agent1 = ConversableAgent("a1", max_consecutive_auto_reply=0, human_input_mode="NEVER")
@@ -177,6 +188,7 @@ def add_num(num_to_be_added):
 
 if __name__ == "__main__":
     test_trigger()
+    test_generate_oai_reply_empty_messages()
     # test_context()
     # test_max_consecutive_auto_reply()
     # test_conversable_agent(pytest.monkeypatch)