6c per thousand tokens, so $2 per maxed out API call
I'm not exactly sure you define that scale, perhaps Minecraft bots or the like, where the damage after complete failure is self contained to perhaps a few dollars or a few hours of human annoyance. I'm sure there are many niches where a 50% success rate of mass generated programs can earn you big bucks.
But in my experience Codex does very limited reasoning about code paths. For the current state of the art, you are almost guaranteed to have catastrophic bugs in any non-trivial programs engineered by prompt.
I tried it with phone number formats and it came up with more than I could.