diff --git a/src/applications/differential/editor/revision/DifferentialRevisionEditor.php b/src/applications/differential/editor/revision/DifferentialRevisionEditor.php
index 2e2a4899b5..5972b5bb2f 100644
--- a/src/applications/differential/editor/revision/DifferentialRevisionEditor.php
+++ b/src/applications/differential/editor/revision/DifferentialRevisionEditor.php
@@ -100,7 +100,7 @@ final class DifferentialRevisionEditor {
   }
 
   public function setAuxiliaryFields(array $auxiliary_fields) {
-    assert_instances_of($auxiliary_fields, 'DifferentialAuxiliaryField');
+    assert_instances_of($auxiliary_fields, 'DifferentialFieldSpecification');
     $this->auxiliaryFields = $auxiliary_fields;
     return $this;
   }
diff --git a/src/applications/differential/view/revisiondetail/DifferentialRevisionDetailView.php b/src/applications/differential/view/revisiondetail/DifferentialRevisionDetailView.php
index 5c52c767b0..229bcc7669 100644
--- a/src/applications/differential/view/revisiondetail/DifferentialRevisionDetailView.php
+++ b/src/applications/differential/view/revisiondetail/DifferentialRevisionDetailView.php
@@ -39,7 +39,7 @@ final class DifferentialRevisionDetailView extends AphrontView {
   }
 
   public function setAuxiliaryFields(array $fields) {
-    assert_instances_of($fields, 'DifferentialAuxiliaryField');
+    assert_instances_of($fields, 'DifferentialFieldSpecification');
     $this->auxiliaryFields = $fields;
     return $this;
   }