What does it mean to call someone a tool?

Question

What does it mean to call someone a tool?

Answer 1

The same as a fool, idiot. It's usually used between friends and is only mildly insulting.

'You're just (only) a tool' means someone is using you for their own purposes. You are being used as a tool.

Answer 2

The person who was called a tool was used.

In a bad way.

I hope that makes sense...

Answer 3

Someone who is useful/used to get the job done.

Derogatory.

Answer 4

They're only good for one thing. They're boring and stiff, and possibly made out of metal. They are good at s******g things and hammering nails. They're obtuse, and plastic, and there's not much point to having them around. They're not fun.

Or they're a fan of rock band Tool. We refuse to be called 'Toolies'.