You
What should an API error body contain?
ChatGPT
A stable machine-readable code, a human sentence, and, when the fault is the client's, which field. Stack traces help nobody outside your team, and a bare 400 turns every integration into guesswork.
You
Any downside worth knowing before I commit?
ChatGPT
It commits you to a format that is tedious to migrate away from later. The first weeks also look worse than doing nothing, which is when most people abandon it.