The toString() methods on DatabaseName and NamespaceString do not include the tenantId. We usually deal with a namespace as db.coll. However, in the __mdb_catalog entries, and the per database views collection catalog entries, namespace is now <tenantId>_db.coll. It's important that this is clearly documented so that new persisted data access methods that are written in future take into account the specially parsing needed to reconstruct the NamespaceString from persisted state; also for namespace comparison.

Documentation points would be class level, and the architecture guide.