How to programmatically check if outbound transfer limit was reached?

I would like a way to detect if my monthly outbound transfer limit was reached, either via an automated action or an API call. My ultimate goal is to detect when this limit is reached and then automatically shut down my API (it is not critical, and I’d rather it be unavailable than racking up extra charges).

As far as I can tell from checking this forum and the API docs, there is currently no way to do this. One endpoint I toyed with was v2/monitoring/metrics/droplet/bandwidth, but this is not the same thing as outbound transfer.

I know that the chance of me hitting my limit is small (I usually don’t get anywhere close to it), but it just makes me uneasy to think that the only thing standing between me and financial ruin is a script that continuously calls my API, so I’d rather be safe than sorry.

I have a billing alert set to $1 above my expected monthly charges so I can manually respond ASAP if needed, but I would rather have a mechanism to shut it down immediately if possible, just for my own peace of mind.