diff --git a/metricflow/query/query_parser.py b/metricflow/query/query_parser.py
index 9d1390936a..b2c6aa4166 100644
--- a/metricflow/query/query_parser.py
+++ b/metricflow/query/query_parser.py
@@ -680,9 +680,7 @@ def _parse_linkable_elements(
             for linkable_element in linkable_elements:
                 parsed_name = StructuredLinkableSpecName.from_name(linkable_element.name)
                 if parsed_name.time_granularity:
-                    raise ValueError(
-                        "Time granularity must be passed in the `grain` attribute for `group_by` query param."
-                    )
+                    raise ValueError("Must use object syntax for `grain` parameter if `date_part` is requested.")
                 structured_name = StructuredLinkableSpecName(
                     entity_link_names=parsed_name.entity_link_names,
                     element_name=parsed_name.element_name,