A Salesforce Administrator is creating a record-triggered flow. When certain criteria are met, the flow must call an Apex method to execute complex validation involving several types of objects…

A Salesforce Administrator is creating a record-triggered flow. When certain criteria are met, the flow must call an Apex method to execute complex validation involving several types of objects. When creating the Apex method, which annotation should a developer use to ensure the method Can be used within the flow?