422 on the real call.
It mirrors the same engine that powers POST /campaigns brief screening, so a pre-check result predicts how the brief will be treated at submission.
All requests use the base URL https://api.interchange.io/api/v2 and a Authorization: Bearer $SCOPE3_API_KEY header.
Task Reference
Check moderation
POST /moderation/check — pre-check text and get findingsAll moderation tasks
Per-operation reference