diff --git a/requirements.txt b/requirements.txt
index 646a5c7..93908dd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-langchain==0.0.257
+langchain==0.0.266
 openai
 sentence_transformers
 fschat==0.2.24
diff --git a/requirements_api.txt b/requirements_api.txt
index 1e13587..f567f9f 100644
--- a/requirements_api.txt
+++ b/requirements_api.txt
@@ -1,4 +1,4 @@
-langchain==0.0.257
+langchain==0.0.266
 openai
 sentence_transformers
 fschat==0.2.24
diff --git a/startup.py b/startup.py
index 830c322..66814ad 100644
--- a/startup.py
+++ b/startup.py
@@ -284,7 +284,7 @@ def parse_args() -> argparse.ArgumentParser:
         dest="model_worker",
     )
     parser.add_argument(
-        "-n"
+        "-n",
         "--model-name",
         type=str,
         default=LLM_MODEL,
@@ -292,7 +292,7 @@ def parse_args() -> argparse.ArgumentParser:
         dest="model_name",
     )
     parser.add_argument(
-        "-c"
+        "-c",
         "--controller",
         type=str,
         help="specify controller address the worker is registered to. default is server_config.FSCHAT_CONTROLLER",