Game concept
Scheme Resistance
The game also links it as Resistance, Hostile Scheme Resistance.
From the game's encyclopedia
The Scheme Resistance of a Character slows down Schemes against them.
The Scheme Phase Length of the Scheme Owner is reduced by this value, increasing the time it takes for the Scheme to gain Advantages.
Scheme Resistance is increased by the corresponding Skill of the Scheme Target and their Spymaster, as well as by the 'Disrupt Schemes' Councillor Task (if the Scheme is Hostile).
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.
Scheme Resistance is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "The Scheme Resistance of a Character slows down Schemes against them." It is part of Scheme. The game also links it as Resistance and Hostile Scheme Resistance. 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.