Capacity
Capacity describes how much of that Capability is actually available within a bounded period, place, quantity, state, or set of conditions.
Specification-sourced: quoted from the governing specification, pending the applicable specification-owner approvals. The specification controls.
In RSMOne's words
A mill may have the Capability to process a grain and still have no Capacity in the month a Formation needs it. Capacity changes with season, place and prior Commitments; the Capability it draws on does not.
What it is not
Capacity ≠ Capability
Capacity is the bounded, available share of a Capability. Keeping them apart prevents theoretical competence from being treated as available supply. 01 §4.3 · Capabilities and Capacity