Adds durability to all weapon items that can be found when a scan is ran on startup. Durability will decrease every time a weapon is used, provided that the weapon fires bullets (this can count for melee weapons too as most melee weapons still fire bullets.) As a weapon loses its durability, it will do less damage and have increased spread.
durability_decrease_scale config value either in the System menu or via command. The default value is set to 1.