How GTM Inboxes uses this term
GTM export processors gate provider uploads on smtpReadiness.canExport and persist per-row failures with failureType smtp_readiness when inboxes are not ready.
Partial success is intentional
A readiness-gated export should not fail the whole batch when only some rows are unsafe. Ready rows can proceed, and blocked rows receive redacted next actions.
What must stay redacted
Export failures must avoid plaintext SMTP passwords, encrypted values, password hashes, provider secrets, raw recipient addresses, and raw upstream payloads.