Agent Passport System This document specifies the Agent Passport System (APS), a protocol for representing and evaluating authority exercised by AI agents. APS separates agent identity, represented principal, delegated authority, policy approval, admission to dispatch, observed results, and external effects. It defines cryptographic identity and principal records, monotonic delegation, revocation and authority- lifecycle semantics, deterministic action and decision references, signed governed-action records, verifier outcomes, evidence resolution, profiles, and protocol bindings. APS defines how an enforcement boundary rechecks current authority before admitting an action to dispatch, and how a verifier distinguishes what a signed record establishes from claims that remain unresolved or external to the protocol. Requirements are split into APS Core, which every conforming implementation carries, and Candidate features, which an implementation opts into by naming them in its claim, and most of the lifecycle and decision-to-effect material in this document is Candidate rather than Core. Candidate features specify additional lifecycle and decision-to-effect behavior without making those features requirements of APS Core conformance. Implementation and conformance sections identify which requirements have exact conformance-vector coverage and which are implemented by the reference implementations. APS does not treat a valid signature, receipt, or delegation chain as proof of external truth or of the absence of an out-of-band execution path.