Capabilities sit inside products. They are used as flags for capabilities that are turned on for every plan. Capabilities allow you to add functionality to every plan at once without needing to worry about setting individual values for each plan.
To add a capability, you only need to decide on a name for it.
If you want to limit the use of a capability within different plans, you can combine them with features. This allows you the flexibility to make changes to your products as you need, either across the entire product, or on a single plan.
Capabilities are not listed in your pricing tables.