Design and code the internal (session scoped) data structures that save the current state of fault points configured. The data structures need to work with the API to be able to set/get the faults and their states. Consider that a fault could be:

• enabled / disabled
• All the faults could be reset to their default state
• A fault might carry a user-provided value
• A fault might carry a state of either being disabled after being hit, or remain enabled all the time (or disable after hitting N times)
• A fault could carry a probability with which it gets hit (fault triggers 1 out of N times that it gets hit)
  .. etc ..

We will need to work along with API definition to be able to provide the data structure that can efficiently manage the faults.