In drafting purchase descriptions for service contracts, agency requiring activities shall ensure that inherently governmental functions (see subpart 7.5) are not assigned to a contractor. These purchase descriptions shall

(a) Reserve final determination for Government officials;

(b) Require proper identification of contractor personnel who attend meetings, answer Government telephones, or work in situations where their actions could be construed as acts of Government officials unless, in the judgment of the agency, no harm can come from failing to identify themselves; and

(c) Require suitable marking of all documents or reports produced by contractors.