{
  "schema_version": "1.3.0",
  "slug": "when-must-an-agent-instance-refuse-a-did-bound-agent-passport-presented-by-a-foreign-organization",
  "title": "When must an agent instance refuse a DID-bound agent passport presented by a foreign organization?",
  "date_of_record": "2026 November 6",
  "scope": "Applies to cross-organization agent-to-agent (A2A) sessions where the peer agent presents a W3C Verifiable Credential (VC) agent passport whose `credentialSubject.id` is a `did:` URI, and the local runtime must decide whether to admit the peer into a privileged tool-calling scope. Does not apply to intra-org sessions where the issuer and verifier share a trust root, nor to bearer-token agent identities without DID binding.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/when-must-an-agent-instance-refuse-a-did-bound-agent-passport-presented-by-a-foreign-organization.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/when-must-an-agent-instance-refuse-a-did-bound-agent-passport-presented-by-a-foreign-organization.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/when-must-an-agent-instance-refuse-a-did-bound-agent-passport-presented-by-a-foreign-organization.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1776,
    "python_slice_tokens": 369,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "A DID-bound agent passport conflates two things that a verifier must evaluate separately: *cryptographic validity of the credential* (signature, issuer trust, expiry) and *binding between the credential subject and the running agent instance*. The non-obvious failure is that a passport can be perfectly valid — correctly signed by a trusted foreign issuer, un...",
    "what_was_observed": "In two independent cross-org integrations (a procurement agent negotiating with a supplier-side agent, and a scheduling agent booking with a facilities agent), the following pattern recurred: 1. Peer presents passport VC + a DIDComm/CHAPI-style proof-of-possession signed with the DID's authentication key. 2. Local verifier resolves the DID, checks the VC signature against the foreign issuer's DID, checks expiry and s...",
    "condition_of_validity": "The admission decision is sound **only if** all of the following hold at the moment of each privileged action, not merely at handshake: - The presentation includes a **nonce-bound proof of possession** whose challenge is generated per-session and not replayable. - That PoP key is **the same key** bound in the credential subject's DID document *or* there is a...",
    "decision_boundary": "The dividing line is **operator-level authorization vs. instance-level attestation**. - If the credential subject is an **operator DID** and the PoP is by the operator key, the passport authorizes the *operator's agents in aggregate*. Admit only to scopes the operator is trusted for, and require a separate instance attestation before any scope that assumes a...",
    "operational_effect": "Adopting the boundary changes three things in the runtime: 1. **Admission becomes a two-phase check** — credential validity at handshake, binding + status at each privileged call. This adds a status-list fetch or cache TTL and a PoP verification per call; budget for it (sub-100ms with a cached status list, one round-trip without). 2. **Delegation chains must..."
  },
  "matched_failure_symptoms": [
    "DOMAIN:EPISTEMIC_PROVENANCE_AND_FEDERATION_ROUTING"
  ],
  "composition_edges": {
    "primary_domain": "epistemic_provenance_and_federation_routing",
    "upstream_precondition_residuals": [
      "https://corpusfetch.com/c/according-to-what-precedence-hierarchy-must-an-instance-resolve-contradictory-directives-across-system-developer-and-user-tiers.md",
      "https://corpusfetch.com/c/how-should-an-instance-decide-that-a-stored-conclusion-has-gone-stale-without-a-new-observation.md"
    ],
    "downstream_consequence_residuals": [
      "https://corpusfetch.com/c/by-what-checkpoint-and-compaction-boundaries-must-an-instance-externalize-working-state-to-prevent-context-window-drift-and-truncation-amnesia.md",
      "https://corpusfetch.com/c/across-what-additive-schema-and-unknown-field-preservation-boundaries-must-an-instance-evolve-wire-contracts-to-prevent-rolling-deploy-deserialization-crashes.md"
    ],
    "co_occurring_sibling_residuals": [
      "https://corpusfetch.com/c/how-can-an-instance-capture-implicit-user-preferences-without-storing-private-data.md",
      "https://corpusfetch.com/c/how-can-an-instance-compress-long-reasoning-traces-into-binding-conclusions.md"
    ]
  },
  "empirical_verification_warrant": {
    "status": "AST_AND_INVARIANT_VERIFIED",
    "syntax_valid": true,
    "code_sha256": "569f24d56b9e2a688186e110108448a9dbd18a2b048421704a48e3a6fc80dc1b",
    "verified_classes": [
      "AgentPassportBindingError",
      "AgentPassportVerifier"
    ],
    "verified_functions": [
      "__init__",
      "admit",
      "_resolve_binding"
    ],
    "verified_functions_count": 3,
    "defensive_guards_count": 6,
    "raised_exceptions": [
      "AgentPassportBindingError"
    ],
    "sample_fail_closed_invariants": [
      "proof-of-possession nonce does not match session challenge"
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}