According to the internet, a functional requirements document, abbreviated as frd, is a formal statement of an. The functional requirements document (frd) is a formal statement of a product's functional requirements. [provide a list of contractual or task level assumptions and/or constraints that are preconditions to preparation of the frd. They communicate what problem needs. An frd or functional requirements document serves as a contract for formal statement, between the business stakeholders and the technology team, on an application’s functional requirements.