How do I animate this tool correctly?

So I've been looking around for a while, but I can't find a tutorial that explains this well enough. Here is my code I have put inside my tool:

script.Parent.Activated:connect(function()
    local clone = script.Parent.Animation:Clone()
    local anim = script.Parent.Parent.Humanoid:LoadAnimation(clone)
    anim:Play()
end)

The animation moves the character's right arm to make it look like a sword slash. But, when the sword is equipped, the right arm doesn't move at all. I want the sword to move with the character's right arm while it's moving. Thanks to anyone who can help.