csrf_origin_refused
An unsafe request carrying the session cookie declared an Origin/Referer that is not a configured portal origin. Checked before the synchronizer so a cross-site attempt is refused without the response revealing whether the token would have matched.
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/csrf_origin_refused",
"title": "…",
"status": 403,
"detail": "…",
"instance": "/v1/…"
}