Game concept
Vassal Directive
The game also links it as Vassal Directives, Directive, Directives.
From the game's encyclopedia
As a Liege, you can issue Directives to your Vassals, influencing their Councillor Tasks and which Buildings they construct.
To issue a Directive, you need to enable it, such as by having 50 or more Opinion with the Vassal. Advanced Government Forms do not require this.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Vassal Directive is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "As a Liege, you can issue Directives to your Vassals, influencing their Councillor Tasks and which Buildings they construct." It is part of Vassal. The game also links it as Vassal Directives, Directive and Directives. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.