import json
from typing import List
from langchain_core.messages import BaseMessage


def format_messages(messages: List[BaseMessage]) -> str:
    formatted = []

    for m in messages:
        role = m.type  # Adjust if your object structure differs
        content = m.content
        content_string = content if isinstance(
            content, str) else json.dumps(content)
        formatted.append(f'<{role}>\n{content_string}\n</{role}>')

    return "\n".join(formatted)