device_authorization_grant_refused
HTTP 400§9.10 Agreements
The device code or route-limited grant is malformed, unknown, expired, unapproved, or already spent. Start a new pairing; this response deliberately does not reveal which fact failed.
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/device_authorization_grant_refused",
"title": "…",
"status": 400,
"detail": "…",
"instance": "/v1/…"
}