Most AI cost tooling is an autopsy. It tells you, in detail, what you already spent — token counts, per-call traces, a

dashboard that turns red after the bill is locked in. None of it does the one thing I kept wanting: refuse the call before

it goes out.

I ran into this building agent tooling. Once I had more than a couple of agents hitting paid APIs on a schedule, two

problems showed up that nothing off the shelf solved cleanly.