{"ok":true,"service":"mailbox-backend","mode":"MAILBOX_BACKEND_OFFICIAL_API_V1","endpoints":["GET /health","GET /mailbox/:user_id","GET /mailbox/:user_id/unread-count","POST /mailbox/:user_id/messages/:message_id/read","POST /mailbox/:user_id/read-all","GET /v2/mailbox/messages","GET /v2/mailbox/unread-count","POST /v2/mailbox/messages/:message_id/read","POST /v2/mailbox/read-all"]}