useful_courtier_or_guest_claim_trigger

useful_courtier_or_guest_claim_trigger = {
	courtier_or_guest_claim_trigger = { RULER = $RULER$ }
	tier < $RULER$.highest_held_title_tier
	$RULER$ = { is_landed = yes }
	OR = { #For distance check
		exists = title_province
		exists = holder.capital_province
	}
	#The higher tier the ruler has, the longer distance is acceptable
	#We prefer to measure against the title's province, but if there is none, check its holder
	trigger_if = {
		limit = { $RULER$ = { highest_held_title_tier >= tier_empire } }
		trigger_if = {
			limit = { exists = title_province }
			title_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_almost_massive } }
		}
		trigger_else = {
			holder.capital_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_almost_massive } }
		}
	}
	trigger_else_if = {
		limit = { $RULER$ = { highest_held_title_tier = tier_kingdom } }
		trigger_if = {
			limit = { exists = title_province }
			title_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_huge } }
		}
		trigger_else = {
			holder.capital_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_huge } }
		}
	}
	trigger_else_if = {
		limit = { $RULER$ = { highest_held_title_tier = tier_duchy } }
		trigger_if = {
			limit = { exists = title_province }
			title_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_large } }
		}
		trigger_else = {
			holder.capital_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_large } }
		}
	}
	trigger_else = {
		trigger_if = {
			limit = { exists = title_province }
			title_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_medium } }
		}
		trigger_else = {
			holder.capital_province = { squared_distance = { target = $RULER$.capital_province value <= squared_distance_medium } }
		}
	}
}

As written in game/common/scripted_triggers/00_courtier_guest_management_triggers.txt.