# MON-04 Drift monitoring

Domain: MON Continuous Monitoring & Human Oversight · HI-AAF v1.3 · Public review · https://humanintel.net/standard/mon/mon-04

Drift monitoring tracks quality scores, refusal rates, and performance on the standing evaluation set over time. Material drift triggers re-assessment under Domain 2.

The agent's behavior is compared against its specification over time through continuous drift monitoring. Quality scores, refusal rates, and performance on the standing evaluation set are tracked. Material drift, a sustained departure from the behavior baseline, triggers re-assessment under Domain 2 and the change-management process under GOV-05.

## Maturity

- L1 Ad hoc: Controls exist informally; documentation is incomplete; no consistent review.
- L2 Documented: Controls are written down; ownership is assigned; review cadence is defined.
- L3 Operated: Controls are followed in practice; evidence is collected; deviations are tracked. Published criterion for MON-04: Drift monitoring is active and tracks the specified metrics; drift thresholds are documented; at least one monitoring cycle has been completed; material drift events have been addressed or no drift has been detected.
- L4 Measured: Control effectiveness is measured against documented thresholds; trends are reported.
- L5 Continuously Improved: Controls evolve based on incident learning; maturity gains are evidenced over time.

## Evidence an assessor asks for

- Drift monitoring is active and tracks the specified metrics.
- Drift thresholds are documented.
- At least one monitoring cycle has been completed.
- Material drift events have been addressed or no drift has been detected.

## Framework mappings

- NIST AI RMF: MANAGE 2.4, MEASURE 3.2
- ISO/IEC 42001: A.9.4
- SOC 2 (TSC): CC7.3
- EU AI Act: Art. 14(4)
- Singapore: MAIGF Incident Reporting

Mappings are directional: meeting this control evidences but does not by itself satisfy the external requirement.

## Related

- Cites GOV-05 Change management authority: https://humanintel.net/standard/gov/gov-05
- Cited by SPC-06 Behavior baseline capture: https://humanintel.net/standard/spc/spc-06
- Glossary: Drift: https://humanintel.net/standard/glossary#drift

## Cite this control

Human Intelligence. HI-AAF v1.3, MON-04 Drift monitoring. Public review edition, July 2026. https://humanintel.net/standard/mon/mon-04