I do not know what this output error "Unable to cast string to token" means? Can someone tell me what it means please, thank you.
hint = game.Workspace.MainScript.hint
hint.Changed:connect(function()
script.Parent.Text = hint.Value
if hint.Value == "" then
script.Parent:TweenPosition(UDim2.new(0, 0, -0.1, 0),"Linear",2.4, "InOut")
else
script.Parent:TweenPosition(UDim2.new(0, 0, 0.1, 0),"Linear", 2.4, "InOut") -- Eror is on this line.
end
end)

4 comments
The code around the line that is throwing that error would be nice to include.
String can only be used in arithmetic if it can be converted to a number. That is what it means. You probably have to put tonumber() around your string if it is a number..
If it could be added in the first place because the string represents a number, the string would actually be forcibly cast to a number without throwing an error. That error would also look something like "attempt to perform arithmetic on a string value" rather than the above.
I added the code