AFAIK, fungi have never used mechanical tools.
They can solve complex algos using parallel processing, but no tools. Unless you consider zombie ants to be a tool...
this behaviour is quite common in cattle and other animals, often seen rubbing or using sticks to scratch spots. sometimes it is dangerous as they find fences with nail poking out and cut themselves when rubbing to to calm an itch.
Having spent my childhood around cows, I can say there's a great deal of doubt in my mind on that point. I know from extensive first-hand experience that cows are quite stupid.
Like most things. . . It's shades of grey.
"... the tool is a detached object (rock) used to procure some thing (food) ordinarily incapable of being accessed without a tool.". Also it is "manipulated independent of its location." [0]
Rubbing against a tree is not tool use. Similarly, dropping a nut on a rock is not tool use, but dropping a rock on a nut is.
It gets a bit more complex: You can pickup a stick and use it (similar to the cow); you can first prepare the stick by stripping leaves and branches off (some primates); you can bend the stick into a useful hook (New Caledonian crows).
Look up corvids and especially New Caledonian crows. they are pretty amazing; in some tasks they apparently outperform all primates except one particular species.
Oh wait, the article says external is in the "scientific definition". Fine.
....wait, no