diff --git a/backend/app/core/tree_validation.py b/backend/app/core/tree_validation.py
index a0c8652d..68918570 100644
--- a/backend/app/core/tree_validation.py
+++ b/backend/app/core/tree_validation.py
@@ -83,17 +83,17 @@ def _validate_node(node: dict[str, Any], path: str, errors: list[dict[str, str]]
             })
 
     elif node_type == "action":
-        if "action" not in node or not node["action"]:
+        if "title" not in node or not node["title"]:
             errors.append({
-                "field": f"{path}.action",
-                "message": "Action nodes must have a non-empty action"
+                "field": f"{path}.title",
+                "message": "Action nodes must have a non-empty title"
             })
 
     elif node_type == "solution":
-        if "solution" not in node or not node["solution"]:
+        if "title" not in node or not node["title"]:
             errors.append({
-                "field": f"{path}.solution",
-                "message": "Solution nodes must have a non-empty solution"
+                "field": f"{path}.title",
+                "message": "Solution nodes must have a non-empty title"
             })
 
     elif node_type == "answer":