BetaScry is based on AlphaScry, a previous addon that implemented filtering for the Antiquities Leads.
AlphaScry allowed you to filter out leads below a certain rarity.
In BetaScry, you can specify both lower and upper rarity - this is useful for those who still didn't max their scrying level - as well as the type of the antiquity, such as Treasure or Furnishing. The list of types comes from the game, and therefore should be localised (whereas other parts of the UI are not).

Future plans (pending on my activity levels): looking into sorting the leads, and to apply a filter by expiry, e.g. leads expiring today, in the next x days, etc.