This was very easy to make.
print("Part counter Plugin Loaded")
local pm = PluginManager()
local plugin = pm:CreatePlugin()
local toolbar = plugin:CreateToolbar("Part count Plugin")
local button = toolbar:CreateButton("PC", "[Part Counter]counts parts that are in the game", "icon.png")
button.Click:connect(function()
game:SetMessageBrickCount()
wait(math.random(3, 5))
game:SetMessage("")
end)