According to page 32 of the Rules Reference under:

USES (X “TYPE”) When a card with this keyword enters play, place X all-purpose counters from the token pool on the card. The word following the value establishes and identifies the type of uses the card holds. Each card with this keyword also has an ability that references the type of use established by the keyword as part of the cost. After the last all-purpose counter is removed from a card with uses (and the effect resolves), discard that card.