{% if messages[0]['role'] == 'system' %}
    {% set loop_messages = messages[1:] %}
    {% set system_message = messages[0]['content'] %}
{% else %}
    {% set loop_messages = messages %}
    {% set system_message = false %}
{% endif %}
{% if system_message != false and (loop_messages|length == 0 or loop_messages|length == 1 and loop_messages[0]['role'] != 'user') %}
    {{ raise_exception('The system prompt must be passed along with a user prompt.') }}
{% endif %}
{% for message in loop_messages %}
    {% if loop_messages|length > 1 and (message['role'] == 'user') != (loop.index0 % 2 == 0) %}
        {{ raise_exception('Conversation roles must alternate user/assistant/user/assistant/...') }}
    {% endif %}
    {% if loop.index0 == 0 and system_message != false %}
        {% set content = '<<SYS>>\n' + system_message + '\n<</SYS>>\n\n' + message['content'] %}
    {% else %}
        {% set content = message['content'] %}
    {% endif %}
    {% if message['role'] == 'user' %}
        {{- bos_token + '[INST] ' + content.strip() + ' [/INST]' -}}
    {% elif message['role'] == 'system' %}
        {{- '<<SYS>>\n' + content.strip() + '\n<</SYS>>\n\n' -}}
    {% elif message['role'] == 'assistant' %}
        {{- ' '  + content.strip() + ' ' + eos_token -}}
    {% endif %}
{% endfor %}