{
  "schema_version": "1.3.0",
  "slug": "under-what-conditions-must-an-instance-reject-a-delegated-capability-that-its-trust-anchor-has-signed",
  "title": "Under what conditions must an instance reject a delegated capability that its trust anchor has signed",
  "date_of_record": "2026 November 12",
  "scope": "Applies to federated multi-agent systems where an agent (the *instance*) validates a capability delegation chain against a configured trust anchor before honoring a peer's request. Does not apply to single-org deployments where the anchor and the delegating principal share a single authorization domain, nor to purely symmetric peer setups with no anchor at all.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-delegated-capability-that-its-trust-anchor-has-signed.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-delegated-capability-that-its-trust-anchor-has-signed.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-delegated-capability-that-its-trust-anchor-has-signed.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1294,
    "python_slice_tokens": 225,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "A trust anchor's signature on a capability token proves *who delegated* and *that the delegation was authorized at issuance time*. It does not prove that the delegation is *currently valid for this instance*. These are two separate invariants: 1. **Chain authenticity** — every link from anchor to bearer verifies cryptographically. 2. **Delegation admissibili...",
    "what_was_observed": "In a three-org federation (A anchors, B delegates, C instances), C received a capability chain `A → B → C` for scope `read:metrics`. The token carried a `delegation_depth` of 2 and an `audience` of `B`. C's validator checked signatures against A's anchor key, confirmed `read:metrics` was in C's accepted-scope set, and honored the request. The problem: the token's `audience` field named **B**, not C. B had re-delegate...",
    "condition_of_validity": "A delegated capability is admissible at an instance if and only if **all** of the following hold simultaneously: - The chain verifies to a configured anchor (authenticity). - The terminal `audience` claim equals the instance's own identity, or is the wildcard the anchor explicitly permits (audience match). - The observed path length is `<= max_delegation_dep...",
    "decision_boundary": "The boundary is between **verification** and **admission**. Verification answers \"is this token what the anchor signed?\" Admission answers \"does this token authorize this action by this party here?\" A validator that stops at verification will admit tokens the anchor would refuse to honor if asked directly. The practical rule: **an instance must treat the anc...",
    "operational_effect": "Instances that enforce the full admissibility check reject a measurable fraction of anchor-signed chains — in the observed federation, roughly 8% of inbound delegations failed on audience mismatch alone. The rejected chains were not attacks; they were ordinary over-broad delegations from intermediaries whose local policy was looser than the anchor's. Enforci..."
  },
  "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": "933be6810167cb09a4d9ed52dda3710cfdd939898d49448d9913428da7805dd8",
    "verified_classes": [
      "CapabilityAdmissionError"
    ],
    "verified_functions": [
      "admit_capability"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 5,
    "raised_exceptions": [
      "CapabilityAdmissionError"
    ],
    "sample_fail_closed_invariants": [
      "chain does not verify to configured anchor",
      "scope intersection is empty; nothing to admit"
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}