diff --git a/.changeset/towering-organic-grouse.md b/.changeset/towering-organic-grouse.md
new file mode 100644
index 00000000..842aca68
--- /dev/null
+++ b/.changeset/towering-organic-grouse.md
@@ -0,0 +1,5 @@
+---
+"stagehand": patch
+---
+
+Fix temperature setting for GPT-5 family of models
diff --git a/stagehand/llm/client.py b/stagehand/llm/client.py
index 855b0fef..ac0ead4a 100644
--- a/stagehand/llm/client.py
+++ b/stagehand/llm/client.py
@@ -110,6 +110,9 @@ def create_response(
         filtered_params = {
             k: v for k, v in params.items() if v is not None or k in kwargs
         }
+        # Fixes parameters for GPT-5 family of models
+        if "gpt-5" in completion_model:
+            filtered_params["temperature"] = 1
 
         self.logger.debug(
             f"Calling litellm.completion with model={completion_model} and params: {filtered_params}",