List dead-letter observations
Cross-tenant operator forensics: returns a keyset-paginated, reverse-chronological page of dead-letter observations captured from the delivery pipeline. This is an operator surface — it authorizes against an operator scope and carries no tenant context. The projection carries no secret, no customer endpoint URL, and no signing material. The tenant_id_raw field is an untrusted, best-effort capture surfaced for forensic value only.
Authorizations
A bearer JWT issued by plugin-auth (lib-auth). The tenant identity is resolved from the validated token claims; the /v1 surface never reads a tenant from the body, path, or query. Machine callers obtain a token via the plugin-auth client-credentials flow. The /admin surface authorizes against an operator scope and carries no tenant context.
Query Parameters
Optional filter on the source topic the failed delivery originated from.
Optional filter on the transport error class. An unrecognized value returns 400 invalid_error_class.
The transport error class a dead-letter observation may be filtered on.
serialization, validation, auth, topic_not_found, broker_unavailable, network_timeout, broker_overloaded, context_canceled, unknown Keyset cursor — the id (UUIDv7) of the last row from the previous page. A malformed value returns 400 invalid_cursor.
Response
A page of dead-letter observations.

