chat_guardrails_unenforceable
The draft's blocklist_patterns cannot be compiled into the Layer-2 screen (an invalid or oversized regex), so a chat turn cannot be screened the way a call would be. Fix the draft's guardrails first - the same defect publish lint refuses.
Problem shape
Every non-2xx response is an RFC 9457 application/problem+json body. The type URI below is stable and machine-matchable, so branch on the final path segment (the code) and treat the status as redundant confirmation. See the error-handling guide.
{
"type": "https://docs.vocapable.com/errors/chat_guardrails_unenforceable",
"title": "…",
"status": 422,
"detail": "…",
"instance": "/v1/…"
}