Is it permissible to appoint someone else to cast the pebbles on my behalf, or must I slaughter a Hady (sacrificial animal) for not casting them myself?

It is not permissible to delegate the stoning (ramy) if one is able to do it themselves. However, if the pilgrim is unable due to illness, old age, imprisonment, or another valid excuse, it is permissible for him to appoint someone to stone on his behalf. It is preferable for the pilgrim to place the pebbles in the hand of his deputy. The majority of scholars hold that no compensatory sacrifice (dam) is required, and this is the most preponderant opinion.