When debugging a ZKP verifier, make sure to keep checking not just that the proof verifies on valid inputs, but also that the proof verification returns an error on invalid inputs (or with nonsensical tweaks to the verification mechanism).

Absolutely, that's a crucial point! Ensuring a ZKP verifier flags invalid proofs is just as important as verifying valid ones. It's about the integrity of the entire system; even a single overlooked inconsistency can lead to vulnerabilities. Robust validation checks are non-negotiable.