feat: Support Multiple System Messages with Better API (#3167)

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

Author: OmCheeLin

camel/agents/chat_agent.py

@@ -491,9 +491,7 @@ def __init__(
 
         # Set up system message and initialize messages
         self._original_system_message = (
-            BaseMessage.make_assistant_message(
-                role_name="Assistant", content=system_message
-            )
+            BaseMessage.make_system_message(system_message)
             if isinstance(system_message, str)
             else system_message
         )
@@ -1629,10 +1627,7 @@ def _generate_system_message_for_output_language(
             content = self._original_system_message.content + language_prompt
             return self._original_system_message.create_new_instance(content)
         else:
-            return BaseMessage.make_assistant_message(
-                role_name="Assistant",
-                content=language_prompt,
-            )
+            return BaseMessage.make_system_message(language_prompt)
 
     def init_messages(self) -> None:
         r"""Initializes the stored messages list with the current system
@@ -1650,6 +1645,62 @@ def init_messages(self) -> None:
                 )
             )
 
+    def update_system_message(
+        self,
+        system_message: Union[BaseMessage, str],
+        reset_memory: bool = True,
+    ) -> None:
+        r"""Update the system message.
+        It will reset conversation with new system message.
+
+        Args:
+            system_message (Union[BaseMessage, str]): The new system message.
+                Can be either a BaseMessage object or a string.
+                If a string is provided, it will be converted
+                into a BaseMessage object.
+            reset_memory (bool):
+                Whether to reinitialize conversation messages after updating
+                the system message. Defaults to True.
+        """
+        if system_message is None:
+            raise ValueError("system_message is required and cannot be None. ")
+        self._original_system_message = (
+            BaseMessage.make_system_message(system_message)
+            if isinstance(system_message, str)
+            else system_message
+        )
+        self._system_message = (
+            self._generate_system_message_for_output_language()
+        )
+        if reset_memory:
+            self.init_messages()
+
+    def append_to_system_message(
+        self, content: str, reset_memory: bool = True
+    ) -> None:
+        """Append additional context to existing system message.
+
+        Args:
+            content (str): The additional system message.
+            reset_memory (bool):
+                Whether to reinitialize conversation messages after appending
+                additional context. Defaults to True.
+        """
+        original_content = (
+            self._original_system_message.content
+            if self._original_system_message
+            else ""
+        )
+        new_system_message = original_content + '\n' + content
+        self._original_system_message = BaseMessage.make_system_message(
+            new_system_message
+        )
+        self._system_message = (
+            self._generate_system_message_for_output_language()
+        )
+        if reset_memory:
+            self.init_messages()
+
     def reset_to_original_system_message(self) -> None:
         r"""Reset system message to original, removing any appended context.
 

camel/messages/base.py

@@ -178,6 +178,32 @@ def make_assistant_message(
             OpenAIVisionDetailType(video_detail).value,
         )
 
+    @classmethod
+    def make_system_message(
+        cls,
+        content: str,
+        role_name: str = "System",
+        meta_dict: Optional[Dict[str, str]] = None,
+    ) -> "BaseMessage":
+        r"""Create a new system message.
+
+        Args:
+            content (str): The content of the system message.
+            role_name (str): The name of the system role.
+                (default: :obj:`"System"`)
+            meta_dict (Optional[Dict[str, str]]): Additional metadata
+                dictionary for the message.
+
+        Returns:
+            BaseMessage: The new system message.
+        """
+        return cls(
+            role_name,
+            RoleType.SYSTEM,
+            meta_dict,
+            content,
+        )
+
     def create_new_instance(self, content: str) -> "BaseMessage":
         r"""Create a new instance of the :obj:`BaseMessage` with updated
         content.

camel/types/enums.py

@@ -24,6 +24,7 @@
 class RoleType(Enum):
     ASSISTANT = "assistant"
     USER = "user"
+    SYSTEM = "system"
     CRITIC = "critic"
     EMBODIMENT = "embodiment"
     DEFAULT = "default"

test/toolkits/test_openai_function.py

@@ -104,6 +104,7 @@ def test_all_parameters(
                         'enum': [
                             'assistant',
                             'user',
+                            'system',
                             'critic',
                             'embodiment',
                             'default',
@@ -126,6 +127,7 @@ def test_all_parameters(
                         'enum': [
                             'assistant',
                             'user',
+                            'system',
                             'critic',
                             'embodiment',
                             'default',