diff --git a/dbgpt/util/parameter_utils.py b/dbgpt/util/parameter_utils.py
index c921e9cf3..dc0a08e57 100644
--- a/dbgpt/util/parameter_utils.py
+++ b/dbgpt/util/parameter_utils.py
@@ -637,7 +637,11 @@ def _build_parameter_class(desc: List[ParameterDescription]) -> Type:
         annotations[d.param_name] = _type_str_to_python_type(
             d.param_type  # type: ignore
         )  # Set type annotation
-        fields_dict[d.param_name] = field(default=d.default_value, metadata=metadata)
+        # fields_dict[d.param_name] = field(default=d.default_value, metadata=metadata)
+        if d.param_name == 'ignore_patterns':
+            fields_dict[d.param_name] = field(default=None, metadata=metadata)
+        else:
+            fields_dict[d.param_name] = field(default=d.default_value, metadata=metadata)
 
     # Create the new class. Note the setting of __annotations__ for type hints
     new_class = type(