diff --git a/csst_common/data_manager.py b/csst_common/data_manager.py
index 9ffc98ee648f5c999a5e9a821371b1e7837cd434..e7a99b1c4ba7156d8423032be0b31525886dd2a4 100644
--- a/csst_common/data_manager.py
+++ b/csst_common/data_manager.py
@@ -94,6 +94,8 @@ class CsstMsDataManager:
         The pipeline log file name.
     log_mod : str
         The module log file name.
+    clear_dir : bool
+        If True, clear ``dm.dir_l1`` directory.
 
     Examples
     --------