The rapid deployment of autonomous AI agents creates urgent challenges in the areas of authorization, accountability, and access control in task delegation. This position paper argues that authenticated and auditable delegation of authority to AI agents is a critical component of mitigating practical risks and unlocking the value of agents. To support this argument, we examine how existing web authentication and authorization protocols, as well as natural language interfaces to common access control mechanisms, can be extended to enable secure authenticated delegation of authority to AI agents. By extending OAuth 2.0 and OpenID Connect with agent-specific credentials and using transparent translation of natural language permissions into robust scoping rules across diverse interaction modalities, we outline how authenticated delegation can be achieved to enable clear chains of accountability while maintaining compatibility with established authentication and web infrastructure for immediate compatibility. This work contributes to ensuring that agentic AI systems perform only appropriate actions. It argues for prioritizing delegation infrastructure as a key component of AI agent governance and provides a roadmap for achieving this.