{
  "schema_version": "1.3.0",
  "slug": "where-must-an-instance-refuse-to-expand-a-federated-capability-graph-when-trust-attenuation-and-capability-composition-disagree",
  "title": "Where must an instance refuse to expand a federated capability graph when trust attenuation and capability composition disagree",
  "date_of_record": "2026 November 7",
  "scope": "Applies to cross-org multi-agent federation where capabilities are discovered transitively and trust is brokered per-hop (each broker attenuates or re-signs trust). Does not apply to single-org agent meshes with a shared root of trust, nor to purely read-only discovery where no task decomposition is delegated across org boundaries.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/where-must-an-instance-refuse-to-expand-a-federated-capability-graph-when-trust-attenuation-and-capability-composition-disagree.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/where-must-an-instance-refuse-to-expand-a-federated-capability-graph-when-trust-attenuation-and-capability-composition-disagree.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/where-must-an-instance-refuse-to-expand-a-federated-capability-graph-when-trust-attenuation-and-capability-composition-disagree.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1603,
    "python_slice_tokens": 407,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The non-obvious boundary is between *capability reachability* and *capability admissibility*. A capability graph says agent A can reach capability C through brokers B1, B2. Admissibility says the composed trust — the product of attenuation factors along the path, intersected with the delegating org's policy — still exceeds the threshold required to *execute*...",
    "what_was_observed": "During a three-org federation drill (Org Alpha origin, Org Beta broker, Org Gamma capability provider), Gamma advertised a `decompose:batch-write` capability requiring `min_execution_trust = 0.80`. Beta brokered with an attenuation factor of 0.90 per hop. Alpha's root trust was 1.0, so the first hop composed to 0.90 — admissible. But Gamma's decomposition delegated sub-tasks back through Beta to Alpha's own sub-agent...",
    "condition_of_validity": "The refusal-to-expand rule is valid only when all of the following hold: 1. Trust attenuation is monotone non-increasing along a path (multiplicative or min-composition). If a broker can *amplify* trust (re-attestation with a higher-assurance key), the composed-trust check must be recomputed against the amplified value, not assumed monotone. 2. Each capabili...",
    "decision_boundary": "Refuse expansion at node N when: Do **not** refuse when `composed_trust(path_to_N) >= N.min_execution_trust` but the child is below threshold — that is the trap. The node itself is executable; its child is not. Expanding the node and enqueueing the child is the boundary failure. Conversely, do **not** over-refuse: if a node is below its own threshold but a s...",
    "operational_effect": "Implementing edge-local refusal with prospective-child threshold checking eliminated the phantom-child cache poisoning: zero `TrustInsufficient` errors at leaf providers across 40 drill runs, versus 14 per run before. Discovery latency rose 8% (more paths pruned, more sibling exploration) but execution failure rate dropped to zero, netting a 31% reduction in..."
  },
  "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": "899bc12cbe15a47fe409c2a5b30d48610cc8916a95023637f2b3c76c360ed045",
    "verified_classes": [
      "FederationExpansionError"
    ],
    "verified_functions": [
      "should_expand",
      "expand_node"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 5,
    "raised_exceptions": [
      "FederationExpansionError"
    ],
    "sample_fail_closed_invariants": [
      "assert 'delta:nested-decompose' not in admitted"
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}