diff --git a/src/agentlab/llm/chat_api.py b/src/agentlab/llm/chat_api.py
index 5ecc05ab..371229b5 100644
--- a/src/agentlab/llm/chat_api.py
+++ b/src/agentlab/llm/chat_api.py
@@ -292,7 +292,7 @@ def __call__(self, messages: list[dict], n_samples: int = 1, temperature: float
                     n=n_samples,
                     temperature=temperature,
                     max_tokens=self.max_tokens,
-                    log_probs=self.log_probs,
+                    logprobs=self.log_probs,
                 )
 
                 if completion.usage is None: