Authorization for agent actions should be tiered by a Stakes x Evidence matrix: the rigor of authentication and proof should scale with the financial/operational stakes and with whether the counterparty is known, rather than applying one uniform standard to every agent action.
Engineers often design one authorization mechanism for all agent tool calls. This matrix gives a defensible way to decide when OAuth scopes are sufficient, when shared-vault transaction logs are enough, and when cryptographic signed mandates are required, balancing friction against risk.
Any system granting an AI agent consequential or irreversible actions can categorize those actions by stakes and counterparty trust to choose the appropriate permission and evidence layer.
Authorization requirements depend entirely on the context of stakes and whether parties know each other.
Low-stakes scenarios require minimal proof, while high-stakes unknown counterparty transactions require verifiable cryptographic proofs.
Closed ecosystems simplify dispute handling via transaction logs, reducing the need for heavy cryptographic proofs.