diff --git a/src/agentlab/llm/base_api.py b/src/agentlab/llm/base_api.py
index 9c1ebf5f..b6d1a7be 100644
--- a/src/agentlab/llm/base_api.py
+++ b/src/agentlab/llm/base_api.py
@@ -21,6 +21,7 @@ class BaseModelArgs(ABC):
     max_new_tokens: int = None
     temperature: float = 0.1
     vision_support: bool = False
+    log_probs: bool = False
 
     @abstractmethod
     def make_model(self) -> AbstractChatModel:
diff --git a/src/agentlab/llm/chat_api.py b/src/agentlab/llm/chat_api.py
index 7392e666..bf3380b2 100644
--- a/src/agentlab/llm/chat_api.py
+++ b/src/agentlab/llm/chat_api.py
@@ -87,6 +87,7 @@ def make_model(self):
             model_name=self.model_name,
             temperature=self.temperature,
             max_tokens=self.max_new_tokens,
+            log_probs=self.log_probs,
         )
 
 
@@ -100,6 +101,7 @@ def make_model(self):
             model_name=self.model_name,
             temperature=self.temperature,
             max_tokens=self.max_new_tokens,
+            log_probs=self.log_probs,
         )
 
 
@@ -115,6 +117,7 @@ def make_model(self):
             temperature=self.temperature,
             max_tokens=self.max_new_tokens,
             deployment_name=self.deployment_name,
+            log_probs=self.log_probs,
         )
 
 
@@ -225,6 +228,7 @@ def __init__(
         client_class=OpenAI,
         client_args=None,
         pricing_func=None,
+        log_probs=False,
     ):
         assert max_retry > 0, "max_retry should be greater than 0"
 
@@ -233,6 +237,7 @@ def __init__(
         self.max_tokens = max_tokens
         self.max_retry = max_retry
         self.min_retry_wait_time = min_retry_wait_time
+        self.logprobs = log_probs
 
         # Get the API key from the environment variable if not provided
         if api_key_env_var:
@@ -279,6 +284,7 @@ def __call__(self, messages: list[dict], n_samples: int = 1, temperature: float
                     n=n_samples,
                     temperature=temperature,
                     max_tokens=self.max_tokens,
+                    logprobs=self.logprobs,
                 )
 
                 if completion.usage is None:
@@ -308,7 +314,10 @@ def __call__(self, messages: list[dict], n_samples: int = 1, temperature: float
             tracking.TRACKER.instance(input_tokens, output_tokens, cost)
 
         if n_samples == 1:
-            return AIMessage(completion.choices[0].message.content)
+            res = AIMessage(completion.choices[0].message.content)
+            if self.logprobs:
+                res["logprobs"] = completion.choices[0].logprobs
+            return res
         else:
             return [AIMessage(c.message.content) for c in completion.choices]
 
@@ -328,6 +337,7 @@ def __init__(
         max_tokens=100,
         max_retry=4,
         min_retry_wait_time=60,
+        log_probs=False,
     ):
         super().__init__(
             model_name=model_name,
@@ -339,6 +349,7 @@ def __init__(
             api_key_env_var="OPENAI_API_KEY",
             client_class=OpenAI,
             pricing_func=tracking.get_pricing_openai,
+            log_probs=log_probs,
         )
 
 
@@ -351,6 +362,7 @@ def __init__(
         max_tokens=100,
         max_retry=4,
         min_retry_wait_time=60,
+        log_probs=False,
     ):
         client_args = {
             "base_url": "https://openrouter.ai/api/v1",
@@ -366,6 +378,7 @@ def __init__(
             client_class=OpenAI,
             client_args=client_args,
             pricing_func=tracking.get_pricing_openrouter,
+            log_probs=log_probs,
         )
 
 
@@ -379,6 +392,7 @@ def __init__(
         max_tokens=100,
         max_retry=4,
         min_retry_wait_time=60,
+        log_probs=False,
     ):
         api_key = api_key or os.getenv("AZURE_OPENAI_API_KEY")
         endpoint = os.getenv("AZURE_OPENAI_ENDPOINT")
@@ -399,6 +413,7 @@ def __init__(
             client_class=AzureOpenAI,
             client_args=client_args,
             pricing_func=tracking.get_pricing_openai,
+            log_probs=log_probs,
         )
 
 
@@ -412,6 +427,7 @@ def __init__(
         temperature: Optional[int] = 1e-1,
         max_new_tokens: Optional[int] = 512,
         n_retry_server: Optional[int] = 4,
+        log_probs: Optional[bool] = False,
     ):
         super().__init__(model_name, base_model_name, n_retry_server)
         if temperature < 1e-3:
@@ -422,4 +438,4 @@ def __init__(
             token = os.environ["TGI_TOKEN"]
 
         client = InferenceClient(model=model_url, token=token)
-        self.llm = partial(client.text_generation, max_new_tokens=max_new_tokens)
+        self.llm = partial(client.text_generation, max_new_tokens=max_new_tokens, details=log_probs)
diff --git a/src/agentlab/llm/llm_utils.py b/src/agentlab/llm/llm_utils.py
index 2bbf219d..d6f9e822 100644
--- a/src/agentlab/llm/llm_utils.py
+++ b/src/agentlab/llm/llm_utils.py
@@ -382,9 +382,10 @@ def image_to_jpg_base64_url(image: np.ndarray | Image.Image):
 
 
 class BaseMessage(dict):
-    def __init__(self, role: str, content: Union[str, list[dict]]):
+    def __init__(self, role: str, content: Union[str, list[dict]], **kwargs):
         self["role"] = role
         self["content"] = deepcopy(content)
+        self.update(kwargs)
 
     def __str__(self, warn_if_image=False) -> str:
         if isinstance(self["content"], str):