diff --git a/trinity/common/config.py b/trinity/common/config.py
index c168bb48b1..fbb1c2d148 100644
--- a/trinity/common/config.py
+++ b/trinity/common/config.py
@@ -49,6 +49,8 @@ class FormatConfig:
     # for unpaired preference dataset
     label_key: str = ""
 
+    use_base_format: bool = False
+
 
 @dataclass
 class GenerationConfig:
diff --git a/trinity/common/workflows/workflow.py b/trinity/common/workflows/workflow.py
index 603bd1ced4..1ec255f13f 100644
--- a/trinity/common/workflows/workflow.py
+++ b/trinity/common/workflows/workflow.py
@@ -190,12 +190,27 @@ def format_messages(self):
             messages.append({"role": "assistant", "content": self.reply_prefix})
         return messages
 
+    def format_prompt(self):
+        prompt_text = ""
+        if self.system_prompt:
+            prompt_text += self.system_prompt
+            prompt_text += "\nTask:\n" + self.task_desc + "\nResponse:\n"
+        else:
+            prompt_text += "\nTask:\n" + self.task_desc + "\nResponse:\n"
+        return prompt_text
+
     def run(self) -> List[Experience]:
         # TODO: Optimize the generate function
-        messages = self.format_messages()
+        if self.format_args.use_base_format:
+            prompt_text = self.format_prompt()
+        else:
+            messages = self.format_messages()
 
         logger.debug("start chat")
-        responses = self.model.chat(messages, **self.rollout_args)
+        if self.format_args.use_base_format:
+            responses = self.model.generate([prompt_text], **self.rollout_args)
+        else:
+            responses = self.model.chat(messages, **self.rollout_args)
         for response in responses:
             reward = self.reward_fn(  # type: ignore [misc]
                 response=response.response_text,  # type: ignore [arg-type]