{
  "schema_version": "1.3.0",
  "slug": "why-does-an-instance-identity-rotation-silently-invalidate-in-flight-delegated-tokens-in-zero-trust-multi-agent-meshes",
  "title": "Why does an instance identity rotation silently invalidate in-flight delegated tokens in zero-trust multi-agent meshes",
  "date_of_record": "2026 November 10",
  "scope": "Applies to multi-agent meshes where each agent instance mints short-lived bearer tokens (JWTs or macaroons) bound to a rotating instance identity, and where those tokens are delegated downstream across at least one hop. Does not apply to long-lived service-account credentials, single-hop request/response calls with no delegation, or meshes that re-issue tokens on every hop rather than propagating them.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/why-does-an-instance-identity-rotation-silently-invalidate-in-flight-delegated-tokens-in-zero-trust-multi-agent-meshes.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/why-does-an-instance-identity-rotation-silently-invalidate-in-flight-delegated-tokens-in-zero-trust-multi-agent-meshes.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/why-does-an-instance-identity-rotation-silently-invalidate-in-flight-delegated-tokens-in-zero-trust-multi-agent-meshes.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1286,
    "python_slice_tokens": 198,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The failure is not \"token expiry.\" It is the distinction between **token validity** (the token's own `exp`/`nbf` and signature) and **binding validity** (whether the token's subject identity still corresponds to a live, authoritative instance identity at the verifier). A token can be cryptographically valid, unexpired, and correctly signed, yet be rejected —...",
    "what_was_observed": "During a rolling rotation window (default 90s overlap), a supervisor agent minted a delegation token `T` for a worker agent at `t0`. The token carried `iss=instance-A`, `exp=t0+300s`. At `t0+40s`, instance A rotated: signing key `K_A` was retired, `K_A'` published, and the identity directory marked `instance-A` as superseded by `instance-A'`. At `t0+120s` the worker presented `T` to a tool server. The tool server: 1....",
    "condition_of_validity": "The invariant that must hold for safe delegation across rotation is: > For every delegated token `T` with subject `s`, the verifier must be able to resolve `s` to the *exact* identity (key lineage, policy attachment, and revocation epoch) that was authoritative at `T`'s minting time, for the entire lifetime of `T` — or `T` must be rejected before use. This h...",
    "decision_boundary": "Choose the strategy by token lifetime versus rotation overlap: - If `max_token_lifetime <= rotation_overlap`, current-state directory resolution is safe; the token cannot outlive its identity. - If `max_token_lifetime > rotation_overlap` (the common case), you must either (a) maintain an append-only identity ledger and resolve `sub` at `iat`, or (b) force re...",
    "operational_effect": "In production this presents as intermittent, rotation-correlated authorization failures that do not reproduce under load tests (which rarely span a rotation), and as rare privilege-widening incidents that are nearly invisible in logs because the call *succeeds*. Mitigation: emit the resolved identity lineage alongside every authorization decision, alert when..."
  },
  "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": "723a56b70223c7d5de5665f4e0f5060dc7be31eb7eeaedffe4f4ca098040b3b6",
    "verified_classes": [
      "IdentityRotationBindingError"
    ],
    "verified_functions": [
      "authorize_delegated_token"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 5,
    "raised_exceptions": [
      "IdentityRotationBindingError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}