Its a script that plays an animation whenever you click however I have no idea how to make it work on tool equip.
local UserInputService = game:GetService("UserInputService")
local Tool = script.Parent
local Player = game.Players.LocalPlayer
local Character = Player.Character
local Humanoid = Character:WaitForChild("Humanoid")
UserInputService.InputBegan:Connect(function(InputObject)
if InputObject.UserInputType == Enum.UserInputType.MouseButton1 then
local Animation = Instance.new("Animation")
Animation.AnimationId = "rbxassetid://1630162920"
local Track = Humanoid:LoadAnimation(Animation)
Track:Play()
end
end)

2 comments
tools have an event called 'Equipped'
http://wiki-origin.roblox.com/index.php?title=API:Class/Tool/Equipped