Isolation at the query
Every tenant-scoped read filters by organisation in the SQL, not in application logic. An execution id alone is never enough to read another tenant's manifest — verified with a real second tenant, which receives a 404 rather than a 403, so the response does not even confirm the id exists.
Disjoint machine credentials
API key scopes are disjoint, not hierarchical: an admin key cannot execute inference and a data key cannot configure. Neither is a superset, so a compromised key of either kind is bounded rather than merely limited.
Deny-all at the database
Row Level Security is enabled with no permissive policies on every table. The application connects through a privileged path by design; the anon surface reads nothing.