diff --git a/py/src/braintrust/wrappers/anthropic.py b/py/src/braintrust/wrappers/anthropic.py
index 8357fc1e..e14e971a 100644
--- a/py/src/braintrust/wrappers/anthropic.py
+++ b/py/src/braintrust/wrappers/anthropic.py
@@ -37,6 +37,7 @@ def accumulate_event(event=None, current_snapshot=None, **kwargs):
     "tool_choice",
     "tools",
     "stream",
+    "thinking",
 )