diff --git a/shogi-ai/agents/mcts_agent.py b/shogi-ai/agents/mcts_agent.py
index b4c00bd..f32448c 100644
--- a/shogi-ai/agents/mcts_agent.py
+++ b/shogi-ai/agents/mcts_agent.py
@@ -49,7 +49,9 @@ def get_child_from_move(self, move: Move):
             if child.move == move:
                 return child
         logger.warning(
-            "{move} not in tree:\n %s", {[str(child.move) for child in all_children]}
+            "%s not in tree:\n %s",
+            str(move),
+            str([str(child.move) for child in all_children]),
         )
         return None