problem

The body as the problem the server answered (application/problem+json), its members typed: the Problem.status, the error Problem.code, the Problem.violations, the rejected command's Problem.result, the aggregate's Problem.version, what a retry may do (Problem.retry, with Retry-After, seconds or an HTTP date, as Problem.retryAfter) and every other member as an extension, read as wow-client reads a peer's problem. Null when the answer is not a problem.

val answer = server.http.post("/bank/account/alice/withdraw", """{"amount":0}""")
answer.problem!!.violations.single().path.assert().isEqualTo("amount")