roaming_progress_events_reward_effect

roaming_progress_events_reward_effect = {
	involved_activity = {
		add_activity_log_entry = {
			key = $LOG_KEY$
			tags = { activity_log }
			character = root
			root = {
				if = {
					limit = {
						has_activity_intent = roaming_storyteller_intent
					}
					roaming_fame_reward_event_effect = { VALUE = roaming_reward_fame_small }
				}
				else_if = {
					limit = {
						exists = scope:special_guest
						has_activity_intent = roaming_befriend_intent
					}
					scope:special_guest = {
						reverse_add_opinion = {
							modifier = friendliness_opinion
							target = root
							opinion = 15
						}
						roaming_tally_variable_effect = { TYPE = opinion VALUE = 10 }
					}
					root = {
						reverse_add_opinion = {
							modifier = friendliness_opinion
							target = scope:special_guest
							opinion = 15
						}
						roaming_tally_variable_effect = { TYPE = opinion VALUE = 10 }
					}
				}
				else = {
					stress_and_fulfillment_impact = { base = miniscule_stress_impact_loss }
					roaming_tally_variable_effect = { TYPE = stress VALUE = miniscule_stress_impact_loss }
				}
			}
		}
	}
}

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