How to restore chat history from database for initialMessages?

[joel611]

I would like to save all messages into database and restore the history including tool steps to exactly before user left.
the value from onFinish is not convertible to the form of initialMessages, such as no toolInvocations.

Sample code:

await streamText({
  message: converToCoremessage(message),
  ...
  async onFinish({responseMessages) {
    await saveChat({
      chatId: params.id
      response: responseMessages
    })
  }
})

const history = getHistory(params.id);

const {messages} = useChat({
    initialMessages: history
})