Function usage_cost 

pub fn usage_cost(
    model: &str,
    input: u64,
    output: u64,
    cache_read: u64,
    cache_write: u64,
    cache_write_5m: Option<u64>,
    cache_write_1h: Option<u64>,
) -> f64

Price one request’s usage with the runtime’s pricing table (the same one the engine’s turn cost budget uses), cache reads and writes included.