Swear Fealty

base = 50
modifier = {
	desc = offer_vassalization_interaction_aibehavior_differentfaith_tt
	trigger = {
		scope:actor = {
			NOR = {
				faith = scope:recipient.faith
				rite = {
					rite_has_doctrine = doctrine_pluralism_pluralistic
				}
			}
		}
	}
	add = {
		value = -25
		if = {
			limit = {
				scope:actor.faith = {
					faith_hostility_level = {
						target = scope:recipient.faith
						value >= faith_hostile_level
					}
				}
			}
			add = -10
		}
		if = {
			limit = {
				scope:actor.faith = {
					faith_hostility_level = {
						target = scope:recipient.faith
						value >= faith_evil_level
					}
				}
			}
			add = -25
		}
	}
}
modifier = {
	desc = offer_fealty_interaction_aibehavior_hightier_tt
	trigger = {
		scope:actor = {
			highest_held_title_tier >= tier_kingdom
		}
	}
	add = -10
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_widetitletier_tt
	trigger = {
		scope:actor = {
			tier_difference = {
				target = scope:recipient
				value > 1
			}
		}
	}
	add = 20
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_rightfulvassaltitleholder_tt
	trigger = {
		scope:recipient = {
			is_rightful_liege_of = scope:actor
		}
	}
	add = 25
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_distantrealm_tt
	trigger = {
		scope:actor = {
			NOT = {
				any_neighboring_top_liege_realm_owner = {
					this = scope:recipient
				}
			}
			trigger_if = {
				limit = {
					is_landed = no
				}
				NOT = {
					capital_county.holder = {
						target_is_same_character_or_above = scope:actor
					}
				}
			}
			capital_province = {
				squared_distance = {
					target = scope:recipient.capital_province
					value < 200000
				}
			}
		}
	}
	add = -15
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_remoterealm_tt
	trigger = {
		scope:actor = {
			NOT = {
				any_neighboring_top_liege_realm_owner = {
					this = scope:recipient
				}
			}
			trigger_if = {
				limit = {
					is_landed = no
				}
				NOT = {
					capital_county.holder = {
						target_is_same_character_or_above = scope:actor
					}
				}
			}
			capital_province = {
				squared_distance = {
					target = scope:recipient.capital_province
					value >= 200000
				}
			}
		}
	}
	add = -25
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_rival_tt
	trigger = {
		scope:recipient = {
			has_relation_rival = scope:actor
			NOT = {
				has_relation_nemesis = scope:actor
			}
		}
	}
	add = -10
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_nemesis_tt
	trigger = {
		scope:recipient = {
			has_relation_nemesis = scope:actor
		}
	}
	add = -100
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_dynasty_tt
	trigger = {
		scope:recipient = {
			dynasty = scope:actor.dynasty
		}
	}
	add = 10
}
modifier = {
	add = -5
	desc = cultural_acceptance_interaction_reason
	trigger = {
		scope:actor = {
			NOT = {
				has_same_culture_as = scope:recipient
			}
			culture = {
				cultural_acceptance = {
					target = scope:recipient.culture
					value < 50
				}
			}
		}
	}
}
modifier = {
	add = 5
	desc = speaks_same_language_interaction_reason
	trigger = {
		scope:actor = {
			knows_language_of_culture = scope:recipient.culture
		}
	}
}
modifier = {
	desc = offer_vassalization_interaction_aibehavior_claimant_tt
	trigger = {
		scope:actor.primary_title = {
			scope:recipient = {
				has_claim_on = prev
			}
		}
	}
	add = -15
}
ai_value_modifier = {
	ai_greed = 0.75
	min = 0
}
opinion_modifier = {
	who = scope:recipient
	opinion_target = scope:actor
	multiplier = 0.5
}
modifier = {
	add = {
		value = -10
		if = {
			limit = {
				scope:recipient = {
					has_trait = zealous
				}
			}
			add = -30
		}
		else_if = {
			limit = {
				scope:recipient = {
					has_trait = cynical
				}
			}
			add = 30
		}
	}
	scope:actor = {
		government_has_flag = government_is_feudal
	}
	scope:religious_taxation = yes
	desc = CONTRACT_RELIGIOUS_TAXATION_REASON
}
modifier = {
	add = -40
	scope:actor = {
		government_has_flag = government_is_feudal
	}
	scope:low_obligations = yes
	desc = CONTRACT_LOW_TAXES_REASON
}
modifier = {
	add = 40
	scope:actor = {
		government_has_flag = government_is_feudal
	}
	scope:high_obligations = yes
	desc = CONTRACT_HIGH_TAXES_REASON
}
modifier = {
	add = {
		value = -10
		if = {
			limit = {
				scope:recipient = {
					has_trait = zealous
				}
			}
			add = -30
		}
		else_if = {
			limit = {
				scope:recipient = {
					has_trait = cynical
				}
			}
			add = 30
		}
	}
	scope:actor = {
		government_has_flag = government_is_clan
	}
	scope:religious_exemption_clan = yes
	desc = CONTRACT_RELIGIOUS_EXEMPTION_REASON
}
modifier = {
	add = 10
	desc = cowed_from_visit_interaction_reason
	trigger = {
		scope:actor = {
			has_character_flag = cowed_increased_vassalization_acceptance
		}
	}
}
modifier = {
	add = 100
	desc = CONFEDERATION_CULTURE_REASON
	scope:recipient = {
		is_confederation_member = yes
		culture = {
			this = scope:actor.culture
		}
	}
# … (cut here; the rest is in the file)

As written in game/common/character_interactions/00_character_interactions.txt.