sso_logout_invalid
GET/POST /auth/sso/saml/{connection_id}/slo: the LogoutRequest is unsigned, its signature does not verify with the IdP certificate, or its Issuer, Destination or validity window is wrong (reason). Nothing was ended.
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/sso_logout_invalid",
"title": "…",
"status": 400,
"detail": "…",
"instance": "/v1/…"
}