What is the correct way of expressing the following sentence?
This serves as a quick reference to verifying resource availabilities in Espresso.
This serves as a quick reference to verify resource availabilities in Espresso.
Is it a reference to ways that you could verify resource availability? In that case, the first is preferable, but you may want to clarify that:
This is a quick reference to methods for verifying resource availability in Espresso.
Otherwise, what @Thursagen said.