{
  "schema_version": "1.3.0",
  "slug": "under-what-conditions-must-an-instance-reject-a-verifiable-agent-passport-whose-delegation-chain-is-valid-but-whose-scope-attenuation-is-non-monotonic",
  "title": "Under what conditions must an instance reject a verifiable agent passport whose delegation chain is valid but whose scope attenuation is non-monotonic",
  "date_of_record": "2026 November 10",
  "scope": "Applies to AAIF-compliant verifiers accepting delegated credentials (agent passports) where the holder presents a chain of signed scope attestations. Does not apply to first-party passports issued directly to the acting principal, nor to chains terminated at a hardware-rooted trust anchor with a single delegation hop.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-verifiable-agent-passport-whose-delegation-chain-is-valid-but-whose-scope-attenuation-is-non-monotonic.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-verifiable-agent-passport-whose-delegation-chain-is-valid-but-whose-scope-attenuation-is-non-monotonic.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-verifiable-agent-passport-whose-delegation-chain-is-valid-but-whose-scope-attenuation-is-non-monotonic.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1232,
    "python_slice_tokens": 222,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "A *valid* delegation chain and a *sound* delegation chain are not the same property. Validity is a signature-and-linkage predicate: every link verifies against the issuer's public key, every subject identifier matches the next issuer, and the chain terminates at a trusted root. Soundness is a scope predicate: the effective authority at the leaf must be a sub...",
    "what_was_observed": "In a production AAIF deployment, an agent `planner-7` presented a passport chain of length four: root → orchestrator → sub-orchestrator → planner-7. Each link verified. The leaf scope included `tool:filesystem:write` under path prefix `/tmp/scratch`. The root scope did not include filesystem write at all; the orchestrator hop had *added* it via a re-issuance from a sibling sub-orchestrator that legitimately held `too...",
    "condition_of_validity": "The rejection rule is conditioned on three simultaneous facts: 1. The chain contains at least one *re-issuance* hop — a link whose issuer is not the subject of the immediately preceding link (a branch merge), detectable by comparing `issuer` of link *i* against `subject` of link *i−1*. 2. The effective scope at the leaf is not a subset of the effective scope...",
    "decision_boundary": "The boundary is not \"is the leaf scope a subset of the parent scope\" — that is necessary but insufficient. The correct predicate is: for every pair of links *(i, j)* with *i < j* where link *j* was re-issued from a branch whose ancestor is link *i*, `scope(j) ⊆ scope(i)`. Implementations that walk the chain linearly and check only adjacent pairs will pass no...",
    "operational_effect": "Enforcing the monotonicity predicate across ancestor paths reduced accepted-but-unsound passports from 0.7% of delegated presentations to zero in the audited window, at the cost of rejecting 0.03% of legitimate cross-branch re-issuances that lacked the merge attestation. Those rejections were correct: the issuing sub-orchestrators had been re-provisioned wit..."
  },
  "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": "02e66b065f4e0082467e8f72d5fa299399d5286000494788d56fd57ae2d27408",
    "verified_classes": [
      "NonMonotonicDelegationError"
    ],
    "verified_functions": [
      "verify_monotonic_chain"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 4,
    "raised_exceptions": [
      "NonMonotonicDelegationError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}