fix: web_agent prompt word accumulation model accuracy decreases (camel-ai#2158)

Co-authored-by: luomengling <[email protected]>
Co-authored-by: JINO ROHIT <[email protected]>
Co-authored-by: Wendong-Fan <[email protected]>

Author: 4 people

camel/toolkits/browser_toolkit.py

@@ -1175,6 +1175,8 @@ def _observe(
         message = BaseMessage.make_user_message(
             role_name='user', content=observe_prompt, image_list=[img]
         )
+        r""" Reset the history message of web_agent. Important history information is already included in the history field in observe_prompt."""
+        self.web_agent.reset()
         resp = self.web_agent.step(message)
 
         resp_content = resp.msgs[0].content
@@ -1404,6 +1406,8 @@ def _task_replanning(
 - `if_need_replan`: bool, A boolean value indicating whether the task needs to be fundamentally replanned.
 - `replanned_schema`: str, The replanned schema for the task, which should not be changed too much compared with the original one. If the task does not need to be replanned, the value should be an empty string. 
 """
+        r""" Reset the history message of planning_agent. Important history information is already included in the history field in replanning_prompt."""
+        self.planning_agent.reset()
         resp = self.planning_agent.step(replanning_prompt)
         resp_dict = _parse_json_output(resp.msgs[0].content)