diff --git a/src/google/adk/tools/openapi_tool/common/common.py b/src/google/adk/tools/openapi_tool/common/common.py
index cc3bca7..ffd7877 100644
--- a/src/google/adk/tools/openapi_tool/common/common.py
+++ b/src/google/adk/tools/openapi_tool/common/common.py
@@ -100,6 +100,7 @@ class ApiParameter(BaseModel):
   py_name: Optional[str] = ''
   type_value: type[Any] = Field(default=None, init_var=False)
   type_hint: str = Field(default=None, init_var=False)
+  required: Optional[bool] = None
 
   def model_post_init(self, _: Any):
     self.py_name = (
diff --git a/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py b/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py
index 4d9fa6a..7c78eee 100644
--- a/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py
+++ b/src/google/adk/tools/openapi_tool/openapi_spec_parser/operation_parser.py
@@ -76,6 +76,8 @@ class OperationParser:
         description = param.description or ''
         location = param.in_ or ''
         schema = param.schema_ or {}  # Use schema_ instead of .schema
+        schema.description = description if schema.description is None and description != '' else schema.description
+        required = param.required
 
         self.params.append(
             ApiParameter(
@@ -83,6 +85,7 @@ class OperationParser:
                 param_location=location,
                 param_schema=schema,
                 description=description,
+                required=required
             )
         )
 
@@ -230,7 +233,7 @@ class OperationParser:
     }
     return {
         'properties': properties,
-        'required': [p.py_name for p in self.params],
+        'required': [p.py_name for p in self.params if p.required is not False],
         'title': f"{self.operation.operationId or 'unnamed'}_Arguments",
         'type': 'object',
     }