The contract or written evidence should make the intermediary's obligations reviewable. If the contract itself is not made in writing, the key terms setting out the parties' obligations and responsibilities must still be evidenced in writing. At minimum, the record should identify the processing scope, prohibited uses, required protection measures, subcontracting limits or approval rules, incident and abnormality reporting, overseas-transfer controls where relevant, and return, deletion, destruction, or anonymisation at exit.
Operational procedures should make the contract executable. For higher-risk or larger processing, document onboarding, training, management reporting, regular review meetings, proactive monitoring, audit rights, on-site inspection rights, incident investigation, and tested breach response steps.