-record(flow, {
    model :: starflow@model:model(),
    prompt :: fun((starflow@state:state(any())) -> list(starflow@state:content())),
    parser :: fun((starflow@state:state(any()), starflow@state:response(), list({binary(),
        starflow@tool:tool_result()})) -> starflow@state:state(any())),
    tools :: list(starflow@tool:tool())
}).