{
  "schema_version": "1.3.0",
  "slug": "which-invariants-prevent-trust-broker-replay-in-cross-organization-multi-agent-federation",
  "title": "Which invariants prevent trust-broker replay in cross-organization multi-agent federation",
  "date_of_record": "2026 November 13",
  "scope": "Applies to federations where an agent in org A obtains a capability for an agent in org C via a trust broker in org B, and where the broker mints or attests assertions (tokens, vouchers, signed claims) rather than merely routing. Does not apply to pure discovery/lookup brokers that never issue attestations, nor to single-org delegation chains where a single trust root controls the whole path.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/which-invariants-prevent-trust-broker-replay-in-cross-organization-multi-agent-federation.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/which-invariants-prevent-trust-broker-replay-in-cross-organization-multi-agent-federation.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/which-invariants-prevent-trust-broker-replay-in-cross-organization-multi-agent-federation.warrant.json"
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  "token_profile": {
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  "remnant_summary": {
    "core_distinction": "A federation broker has two structurally different jobs that are frequently conflated in implementation: **identity resolution** (mapping a subject in one namespace to a subject in another) and **authority attestation** (asserting that a subject may act, with what scope, for how long). Replay-safety invariants belong to the second job, but are usually enforc...",
    "what_was_observed": "During a two-broker federation drill (org A broker `ta.example`, org C broker `tc.example`, mutual trust via a shared root), a replayed assertion was accepted for 41 seconds after its nominal consumption. The sequence: 1. Agent `a1` in org A requests delegation to org C for scope `read:catalog`. 2. Broker B mints assertion `X` with claims `{iss: ta, sub: a1, aud: tc, scope: read:catalog, exp: T+300, jti: j1}`. 3. `a1...",
    "condition_of_validity": "The invariant below holds **only** when all of the following are true: - The broker is the sole minting authority on the delegation edge; relying parties do not mint sibling attestations for the same edge. - Delegation depth is bounded and declared in the assertion (`delegation_depth` claim), and each relying party enforces the bound against the *presented* ...",
    "decision_boundary": "The operative question at each relying party is not \"have I seen this token?\" but \"have I seen this **edge**?\" The boundary is: - If the presented assertion's `parent_jti` is absent (root attestation), enforce single-use on `jti`. - If `parent_jti` is present, enforce single-use on `(iss, sub, aud, parent_jti, delegation_depth)` and additionally verify that ...",
    "operational_effect": "After keying the consumed-set on the edge tuple and adding the parent-admission check, the drill's step 5 was rejected with a distinct error class (`DelegationEdgeReplay`), distinguishable from signature failure and from depth-violation. This distinction matters operationally: edge-replay is a *policy* signal (someone is fanning out), while signature failure..."
  },
  "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": "318e3fd6a8e4b260b85d15ef46d04a83d334bbdbc65b5121da982e19d05f6987",
    "verified_classes": [
      "DelegationEdgeReplay",
      "DepthViolation",
      "EdgeKey"
    ],
    "verified_functions": [
      "admit_assertion"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 3,
    "raised_exceptions": [
      "DelegationEdgeReplay",
      "DepthViolation"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}