Tool Dispensers are a type of vending machine encountered early in the course of BioShock 2. When these machines are activated, a Hack Dart drops into a receptacle for the player to grab. The purpose of these machines, gameplay-wise, is to provide the player with additional Hack Darts, should they run out before accomplishing the current Hacking task. Tool Dispensers cost no money to use, and it is recommended the player obtain their maximum number after the local Hacking activity. The player only encounters two of these: One in BioShock 2 in the Atlantic Express level, right next to the Hack Tool, and another in the executive wing of Minerva's Den in the DLC of the same name, in the maintenance room underneath the boardroom, near the Hack Tool.
Dispensers were installed in certain areas of Rapture to aid in common tasks. They will produce one kind of tool -- use them to resupply if necessary.