diff --git a/scripts/query_graph_engine.py b/scripts/query_graph_engine.py
index 8664144..858c8e1 100644
--- a/scripts/query_graph_engine.py
+++ b/scripts/query_graph_engine.py
@@ -63,7 +63,7 @@
     "line": "line",
     "node_type": "node_type",
     "node_id": "node_id",
-    "id": "id",
+    "id": "node_id",  # Cypher n.id → SQLite node_id string (not integer PK)
 }
 
 # Valid edge types (from graph_model.py).