{
  "schema_version": "1.3.0",
  "slug": "when-must-an-instance-reject-a-delegated-aaif-capability-token-whose-delegation-chain-is-structurally-valid-but-whose-sc",
  "title": "When must an instance reject a delegated AAIF capability token whose delegation chain is structurally valid but whose scope attenuation is non-monotonic?",
  "date_of_record": "2026 November 6",
  "scope": "Applies to AAIF resource servers validating scoped capability tokens presented across a delegation chain of length ≥ 2, where each link carries an explicit `scope` set and a `delegated_by` signature. Does not apply to root-issued tokens (chain length 1), to opaque bearer tokens, or to tokens whose scopes are governed by an external PDP rather than embedded attenuation.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/when-must-an-instance-reject-a-delegated-aaif-capability-token-whose-delegation-chain-is-structurally-valid-but-whose-sc.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-reject-a-delegated-aaif-capability-token-whose-delegation-chain-is-structurally-valid-but-whose-sc.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/when-must-an-instance-reject-a-delegated-aaif-capability-token-whose-delegation-chain-is-structurally-valid-but-whose-sc.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1472,
    "python_slice_tokens": 194,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "AAIF defines two independent validity predicates on a delegated token: **chain integrity** (every link is signed by its predecessor's key, the chain terminates at a trusted root authority, and no link is expired or revoked) and **scope monotonicity** (the effective scope of link *n* is a subset of the effective scope of link *n−1*, transitively down to the r...",
    "what_was_observed": "In a three-link chain — root `R` (scopes `{read:orders}`), delegate `A` (scopes `{read:orders, write:orders}`), leaf `B` (scopes `{read:orders}`) — a conforming verifier using intersection semantics returned effective scope `{read:orders}` and issued an allow. The chain is non-monotonic at link `A`: `A` claims `write:orders`, which `R` never granted. The intersection erased `write:orders` at the leaf, so no over-priv...",
    "condition_of_validity": "The rejection rule is valid when all of the following hold: 1. The token carries an explicit, signed `scope` set per link (not a scope *reference* resolved out-of-band). 2. The chain is presented in full (`R, A, B, …`) with verifiable signatures at every link. 3. The verifier is the authority of record for the root grant's scope set, or can fetch it from the...",
    "decision_boundary": "Reject the token (do not attenuate, do not allow) when, walking the chain from root to leaf, any link *k* has `scope[k] ⊄ scope[k−1]`. The boundary is strict subset, not equality: legitimate re-delegation narrows scope, and narrowing is monotone. Equality is permitted (a pass-through link). Any element present in `scope[k]` and absent in `scope[k−1]` is a mo...",
    "operational_effect": "Enforcing strict monotonicity converts a silent authorization-integrity fault into a loud, auditable rejection. The operational cost is that misconfigured delegators (which over-broaden a child's scope \"for convenience\" and rely on leaf intersection to clamp it) begin failing closed — this is the intended behavior and surfaces the misconfiguration at delegat..."
  },
  "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": "8f3251986b0d25d876815a651fca37d4b59702a14b80bb0a21419d1c0fe4455e",
    "verified_classes": [
      "AAIFMonotonicityViolation",
      "ChainLink"
    ],
    "verified_functions": [
      "validate_delegation_chain"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 3,
    "raised_exceptions": [
      "AAIFMonotonicityViolation"
    ],
    "sample_fail_closed_invariants": [
      "empty delegation chain"
    ],
    "stdlib_dependencies": [
      "dataclasses",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}