From IFWiki

A puzzlefest is a work of interactive fiction where the player is mainly tasked with solving puzzles in order to proceed.

Traditional older text adventures are generally puzzlefests, with a more or less linear series of challenges to be overcome (often involving finding objects and determining their uses in specific locations, e.g. a key to unlock a door). In contrast, more recent works typically focus on the player's subjective experience, may employ artistic and literary devices such as surrealism, and might have no clearly defined goal, or an ending that is somehow ambiguous.

See also