Tools are items used to repair or manipulate certain world entities. This can include repairing vehicles, construction and deconstruction.
The crowbar is generally used for destructive actions such as removing Defences or Tents, or breaking the locks on Vehicle doors or trunks.
The Wrench, Screwdriver and Hammer are used to repair vehicles, construct defences and craft other items. The Screwdriver and Hammer can be used to construct Defences in two different poses.