Use them together rather than choosing one. The NIST AI Risk Management Framework gives a risk operating model, ISO/IEC 42001 provides a certifiable management system and third-party audit signal, the EU AI Act sets binding obligations if you operate in or serve the EU, and OWASP and MITRE ATLAS list specific agent threats to control. None was written for autonomous agents, so extend them with an enforcement layer that applies policy at the point of action. The frameworks define duties; the control plane enforces them.