Before approval, keep the draft, annexes, emails, meeting notes and internal sign-offs in a versioned file. Record who proposed the clause, which businesses are involved, which employee groups are covered and what protection is said to justify it.
For an agreement already in operation, include hiring freezes, refusals, forwarded applications, instructions to recruiting teams and contacts with recruiters in the chronology. Link each event to an employer, an affected person, a date and a specific rule.
Preserve original files and metadata. A later summary can make review harder if it obscures questions about scope, duration or practical effects. Evidence preservation should be organised separately from later litigation or authority communications.