Chat history data in final prompt

[derevyan]

I just find that chat history in final request look like that -
<CHAT HISTORY> [HumanMessage(content='Message one'), AIMessage(content='Hey'), HumanMessage(content='Message two')] </CHAT HISTORY>

i a bit confused, it how it should looks, is it correct?
As i remember i was something like this before:
AI:message \n USER:Text Message

Can anyone clarify this for me?

P.S.: Does anyone have information on how models like OpenAI, Anthropic, or Gemini are trained to understand conversation history?

My research gives me this ideas:

  {
    "chat_history": [
      {"role": "user", "content": "Message one"},
      {"role": "ai", "content": "Hey"},
      {"role": "user", "content": "Message two"}
    ]
  }

USER: Message one
AI: Hey
USER: Message two

<conversation>
  <user>Message one</user>
  <ai>Hey</ai>
  <user>Message two</user>
</conversation>

Langchain use its own history structure for a reason?

langchain = "^0.2.5"
langchain-core = "^0.2.9"
langchain-community = "^0.2.5"