begin_scheme_basic_effect

begin_scheme_basic_effect = {
	# Log our scheme launcher so that we can refer to them down the line.
	save_scope_as = scheme_launcher
	# Log all the currently on-going schemes.
	## We do it this way being we can't guarantee mutually exclusive targets with non-character scheme targets any more: we can't just look for "X's murder scheme against Y", because X might be plotting against no target whatsoever and have multiple schemes of that type against nothing.
	every_scheme = { add_to_list = current_schemes_list }
	# Now start the scheme.
	start_scheme = {
		type = $SCHEME_TYPE$
		$TARGET_TYPE$ = $TARGET_SCOPE$
	}
	# And grab the scheme's scope.
	random_scheme = {
		limit = {
			NOT = { is_in_list = current_schemes_list }
		}
		save_scope_as = new_scheme
	}
	scope:new_scheme ?= {
		if = {
			limit = {
				exists = scope:actor
				exists = scope:puppet_or_actor
				scope:is_puppet_action ?= yes
				scheme_owner = scope:puppet_or_actor
			}
			set_variable = {
				name = commanding_puppeteer
				value = scope:actor
			}
		}
		# If we have a custom charge threshold to complete, set that here.
		## Sway.
		if = {
			limit = { scheme_type = sway }
			set_variable = {
				name = custom_charge_threshold
				value = 5
			}
		}
	}
}

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