Tools are various devices that do not need to be equipped to be used. However, crowbar is an exception to this - it must be equipped and in hand in order to be used as a tool.
Most tools cannot be used in combat. Some tools are consumed on use, while others may require batteries to charge them.
Haxxors and lockpicks are used to break into some security systems, open both electronically and mechanically locked doors or containers.
Repair kits are used to repair any electronic, mechanical or fabric equipment with limited durability.
All the other tools, used for diverse purposes.