{
  "schema_version": "1.3.0",
  "slug": "which-invariants-prevent-scope-escalation-in-aaif-verifiable-credential-delegation-chains-under-partial-revocation",
  "title": "Which invariants prevent scope escalation in AAIF verifiable credential delegation chains under partial revocation",
  "date_of_record": "2026 November 10",
  "scope": "Applies to AAIF v1.x credential issuance where a root issuer delegates scoped authority through two or more intermediate agents and any link may be revoked independently. Does not apply to single-hop delegation, to credentials issued under a monotonic-append-only revocation log, or to scope models that are not subset-closed.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/which-invariants-prevent-scope-escalation-in-aaif-verifiable-credential-delegation-chains-under-partial-revocation.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/which-invariants-prevent-scope-escalation-in-aaif-verifiable-credential-delegation-chains-under-partial-revocation.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/which-invariants-prevent-scope-escalation-in-aaif-verifiable-credential-delegation-chains-under-partial-revocation.warrant.json"
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  "token_profile": {
    "full_markdown_tokens": 1385,
    "python_slice_tokens": 241,
    "warrant_slice_tokens": 220
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  "remnant_summary": {
    "core_distinction": "The critical distinction is between **scope containment** (the delegated scope is a subset of the parent scope at issuance time) and **scope preservation under revocation** (the delegated scope remains a subset of the *currently valid* parent scope after any ancestor link is revoked). AAIF verification mandates the first and is silent on the second. A chain ...",
    "what_was_observed": "In a three-hop chain — issuer `I` → agent `A` → agent `B` → agent `C` — the credential issued to `B` carried scope `{read, write}` and the credential issued to `C` carried scope `{read}`. `A`'s credential to `B` was revoked at T1 because `A`'s own authorization to grant `write` was withdrawn. A verifier at T2 received `C`'s credential plus the full chain. Each signature verified against its issuer's public key, each ...",
    "condition_of_validity": "The invariant that prevents this is **transitive scope monotonicity under revocation**: > For every credential `c` in chain `c_0 → c_1 → … → c_n`, if `c_i` is revoked, then every credential `c_j` with `j > i` is treated as revoked for verification purposes, regardless of its own revocation status. This is the operational meaning of \"revocation cascades forwa...",
    "decision_boundary": "The boundary is between **reject-on-any-ancestor-revocation** and **reject-only-on-self-revocation**. The former is safe and is the AAIF-conformant reading; the latter is what several early verifier implementations shipped and is unsafe. The decision rule for an agent evaluating a presented chain: 1. Resolve the chain root-to-leaf via `parentCredentialId` bi...",
    "operational_effect": "The observable effect of getting this wrong is silent privilege retention: an agent continues to act under a scope that a human operator believed had been withdrawn, because the withdrawal was applied to an intermediate link and the leaf's own status was clean. In audit logs this appears as a gap — the revoked credential shows as revoked, the leaf shows as v..."
  },
  "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": "a96918403fa29029cd3b96e8275973c0d6b2b37fbb8c63b59fa3f6ce0392d7cd",
    "verified_classes": [
      "DelegationCascadeError"
    ],
    "verified_functions": [
      "verify_chain"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 5,
    "raised_exceptions": [
      "DelegationCascadeError"
    ],
    "sample_fail_closed_invariants": [
      "empty chain presented"
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}