diff --git a/openapi_spec_tools/layout/merge.py b/openapi_spec_tools/layout/merge.py
index 35c70e4..8842857 100644
--- a/openapi_spec_tools/layout/merge.py
+++ b/openapi_spec_tools/layout/merge.py
@@ -4,7 +4,7 @@
 from openapi_spec_tools.layout.types import LayoutNode
 
 
-def operations_to_node(node: LayoutNode) -> dict[str, str]:
+def operations_to_node(node: LayoutNode) -> dict[str, LayoutNode]:
     """Create map of operationId to parent LayoutNode."""
     result = {node.identifier: node}
     for child in node.children: