OptionalmetadataHow vector metadata is shaped (undefined ⇒ the curated default set).
OptionalvectorThe entity this source declares its vectors to be, from ContentSource.Configuration. Read only
to decide whether the per-vector Entity key can be omitted (AutotagBaseEngine.canOmitEntityMetadataKey);
the value itself is never written to metadata, and search validates it at attribution time.
Vector-storage behavior resolved for a single content item, derived from its ContentSource configuration (falling back to its ContentType defaults, then hardcoded defaults). Produced by AutotagBaseEngine.resolveItemVectorStorageConfig.