diff --git a/onnxscript/rewriter/pattern.py b/onnxscript/rewriter/pattern.py
index ef61a8e3b..ddff1b93b 100644
--- a/onnxscript/rewriter/pattern.py
+++ b/onnxscript/rewriter/pattern.py
@@ -959,6 +959,7 @@ def _match_node(self, pattern_node: NodePattern, node: ir.Node) -> bool:
 
         self._matched[pattern_node] = node
 
+        # Note: Need to revisit this to handle optional trailing inputs better. 
         if len(node.inputs) != len(pattern_node.inputs):
             return self.fail("Input nums mismatch. {len(node.inputs)} vs {len(pattern_node.inputs)}")