ai_religious_request_blocker_effect

ai_religious_request_blocker_effect = {
	scope:recipient = {
		if = {
			limit = { # AI is requesting from a Player - we don't restrict AI-to-AI
				is_ai = no
				scope:puppet_or_actor = { is_ai = yes }
			}
			# A player Head of Faith receives this at most once every three years, whatever the asker's tier
			add_character_flag = { flag = $INTERACTION$_received_cooldown years = 3 }
			# Not a switch, because unlisted tiers made the blocker always pass and barred emperors
			if = {
				limit = { scope:puppet_or_actor = { highest_held_title_tier >= tier_kingdom } }
				scope:puppet_or_actor = { add_character_flag = { flag = hof_request_cooldown years = 1 } }
			}
			else_if = {
				limit = { scope:puppet_or_actor = { highest_held_title_tier = tier_duchy } }
				scope:puppet_or_actor = { add_character_flag = { flag = hof_request_cooldown years = 2 } }
			}
			else = {
				scope:puppet_or_actor = { add_character_flag = { flag = hof_request_cooldown years = 4 } }
			}
		}
	}
}

As written in game/common/scripted_effects/00_interaction_effects.txt.