Each actor publishes a card with public information on all its public boxes:
public key empty # public key hash group ? store URL * status * account hash * revision entrusted actors ? revision store URL * account hash * other public data
The public key section links the actor's public key.
The optional group section lists all member accounts belonging to the actor group, including the actor itself. The accounts are grouped by store URL (UTF-8 text) and status (active, idle, or revoked).
The account hashes are stored as byte sequences. The corresponding public key can be obtained from the indicated store.
Revision is a timestamp (milliseconds since epoch) stored as unsigned big-endian integer, and used to merge the actor's status during actor group discovery.
If the group section is missing, the actor is considered active and alone.
The optional entrusted actors section lists the actors entrusted by the group, grouped by store URL. The whole list is most-recent merged on revision.
The card may contain other public data, such as a name, a profile picture, a link to a website, or a product catalogue. All this information is unconditionally public.
The total size of the card object should not exceed 10 KiB. Large pieces of data (such as a picture or catalogue) should be stored in separate objects, and linked from the card.