Merge pull request #1197 from phidatahq/fix/make-sure-chat-history-st…

…arts-with-user-message

Make sure chat history added to LLM messages starts with a user message

cookbook/assistants/cli.py

@@ -1,5 +1,12 @@
 from phi.assistant import Assistant
 from phi.tools.duckduckgo import DuckDuckGo
 
-assistant = Assistant(tools=[DuckDuckGo()], show_tool_calls=True, read_chat_history=True)
+assistant = Assistant(
+ tools=[DuckDuckGo()],
+ show_tool_calls=True,
+ read_chat_history=True,
+ debug_mode=True,
+ add_chat_history_to_messages=True,
+ num_history_messages=3,
+)
 assistant.cli_app(markdown=True)

phi/assistant/assistant.py

@@ -848,7 +848,9 @@ def _run(
 
  # -*- Add chat history to the messages list
  if self.add_chat_history_to_messages:
- llm_messages += self.memory.get_last_n_messages(last_n=self.num_history_messages)
+ llm_messages += self.memory.get_last_n_messages_starting_from_the_user_message(
+ last_n=self.num_history_messages
+ )
 
  # -*- Build the User prompt
  # References to add to the user_prompt if add_references_to_prompt is True
@@ -1055,7 +1057,9 @@ async def _arun(
  # -*- Add chat history to the messages list
  if self.add_chat_history_to_messages:
  if self.memory is not None:
- llm_messages += self.memory.get_last_n_messages(last_n=self.num_history_messages)
+ llm_messages += self.memory.get_last_n_messages_starting_from_the_user_message(
+ last_n=self.num_history_messages
+ )
 
  # -*- Build the User prompt
  # References to add to the user_prompt if add_references_to_prompt is True

phi/memory/assistant.py

@@ -74,14 +74,25 @@ def get_chat_history(self) -> List[Dict[str, Any]]:
  """
  return [message.model_dump(exclude_none=True) for message in self.chat_history]
 
- def get_last_n_messages(self, last_n: Optional[int] = None) -> List[Message]:
- """Returns the last n messages in the llm_messages.
+ def get_last_n_messages_starting_from_the_user_message(self, last_n: Optional[int] = None) -> List[Message]:
+ """Returns the last n messages in the llm_messages always starting with the user message greater than or equal to last_n.
 
  :param last_n: The number of messages to return from the end of the conversation.
  If None, returns all messages.
  :return: A list of Messages in the chat_history.
  """
- return self.llm_messages[-last_n:] if last_n else self.llm_messages
+ if last_n is None or last_n >= len(self.llm_messages):
+ return self.llm_messages
+
+ # Iterate from the end to find the first user message greater than or equal to last_n
+ last_user_message_ge_n = None
+ for i, message in enumerate(reversed(self.llm_messages)):
+ if message.role == "user" and i >= last_n:
+ last_user_message_ge_n = len(self.llm_messages) - i - 1
+ break
+
+ # If no user message is found, return all messages; otherwise, return from the found index
+ return self.llm_messages[last_user_message_ge_n:] if last_user_message_ge_n is not None else self.llm_messages
 
  def get_llm_messages(self) -> List[Dict[str, Any]]:
  """Returns the llm_messages as a list of dictionaries."""
@@ -90,12 +101,12 @@ def get_llm_messages(self) -> List[Dict[str, Any]]:
  def get_formatted_chat_history(self, num_messages: Optional[int] = None) -> str:
  """Returns the chat_history as a formatted string."""
 
- messages = self.get_last_n_messages(num_messages)
+ messages = self.get_last_n_messages_starting_from_the_user_message(num_messages)
  if len(messages) == 0:
  return ""
 
  history = ""
- for message in self.get_last_n_messages(num_messages):
+ for message in self.get_last_n_messages_starting_from_the_user_message(num_messages):
  if message.role == "user":
  history += "\n---\n"
  history += f"{message.role.upper()}: {message.content}\n"

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "phidata"
-version = "2.4.39"
+version = "2.4.40"
 description = "Memory, knowledge and tools for LLMs."
 requires-python = ">=3.7"
 readme = "README.md"