Sums the cost of all spans in a trace that have a model recorded.
Examples
tr <- Trace$new("cost-demo")
tr$start()
s1 <- Span$new("call1", type = "llm")
s1$set_model("gpt-4o")
s1$set_tokens(input = 1000L, output = 500L)
tr$add_span(s1)
s2 <- Span$new("call2", type = "llm")
s2$set_model("gpt-4o-mini")
s2$set_tokens(input = 2000L, output = 1000L)
tr$add_span(s2)
tr$end()
trace_total_cost(tr)
#> [1] 0.0084