Ok, a tool, loosely defined, would be an object or instrument used to assist or facilitate a task. The earliest tools were, quite literally, sticks and stones. As technology has evolved, so have tools.

Compare a rock to a shiny new mass-produced hammer. You can build a better house faster now.

Compare a sharpened stick to 30 shiny new mass-produced bullets in a shiny new mass-produced high capacity magazine in a shiny new mass-produced handgun. You can kill more people faster now.

Is an instrument of death your idea of a tool? Do you really want to define a weapon as a tool? Good luck with that.