@techreport{kondoju-evc-02,
    number =    {draft-kondoju-evc-02},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-kondoju-evc/02/},
    author =    {Viswanadha Pratap Kondoju},
    title =     {{An External Verifier Contract for Agent Authorization Decisions}},
    pagetotal = 43,
    year =      2026,
    month =     sep,
    day =       8,
    abstract =  {This document specifies the External Verifier Contract (EVC): a small, testable, proof-system-agnostic boundary between a host (the program about to take a privileged action on an agent's behalf) and an external verifier (a subprocess that renders an allow/deny verdict on an opaque proof bundle). The contract governs only the transport and verdict envelope: how the host hands a single JSON request to a verifier subprocess over stdin, how the verifier answers with exactly one JSON verdict on stdout, and how the host interprets exit codes, timeouts, and malformed output under a fail-closed rule. Three properties make the boundary standardizable: (1) a single-shot subprocess transport with a closed JSON verdict schema; (2) fail- closed host semantics that are independently testable by a host- conformance suite; and (3) proof-system agnosticism, so the same envelope carries classical-signature, zero-knowledge, and third-party verdicts, distinguished only by an OPTIONAL self-description field. EVC is deliberately not a governance framework, not a delegation model, and not a policy language. It is the narrow decision boundary those larger systems all require at the point of enforcement.},
}