This is pretty near:

Detect breaches with Canary credit cards!

TL;DR;

Today we’re releasing a new Canarytoken type: actual credit cards!

1. Head over to canarytokens.org;
2. We give you a valid credit card (number, expiration, and CVC);
3. If anyone ever attempts to use that card you’ll be notified.

https://blog.thinkst.com/2023/01/swipe-right-on-our-new-credit-card-tokens.html

Swipe right on our new credit card tokens!

Thinkst Thoughts
@lojikil Is this good or bad news, I wonder, for vendors of systems that use AI to detect fraud?
@TimWardCam probably minimally impactful news; generally banks use a range of checks for fraud, AML, &c, so I suspect this will be more used on the security side as a signal rather than an input to fraud systems per se
@lojikil My initial guess is that it would be of greatest value to retailers and the like seeking to avoid fines for failing to detect and respond to data breaches fast enough. The killer application would be if regulators starting increasing fines for slow responses to data breaches because "you didn't even use canary cards".