IMO the nicest prompt format is prompt.md.j2. Here we make the messages explicit, and the markdown and jinja syntax obvious

load_md_fm_j2_prompt.py

def split_frontmatter(fm_md_split :str):
    """Load prompt in md.jinja2 format
     
    In this format we have multiple frontmatters and content sections, each defining a message. The idea here is to use jinja formatting in a promt.md.jinja file to make the markdown, and jinja formatting obvious

    e.g.
        ---
        role: system
        ---
        Be good
        ---
        role: user
        ---
        What is the meaning of life?

    usage:
        from jinja2 import FileSystemLoader, FileSystemLoader
        env = Environment(loader=FileSystemLoader("../src/prompts/")) 
        fm_md_split = env.get_template("isekai.md.j2")
        split_frontmatter(fm_md_split.render(content1="Be good", sys="What is the meaning of life?"))

    """
    sections = fm_md_split.split("---\n")[1:]
    # pairs
    messages = []
    for i in range(0, len(sections), 2):
        fm = yaml.safe_load(sections[i])

        # since the only required role is user, make it the default
        if fm is None:
            fm = {'role': 'user'}
        
        message = dict(content=sections[i+1], **fm)
        messages.append(message)
    return messages

file: prompt.md.jinja2

---
role: system
---
{{ system_prompt }}
---
role: user
---
What is the meaning of life?