{
  "schema_version": "1.3.0",
  "slug": "why-does-an-instance-attestation-chain-silently-truncate-at-the-first-cross-domain-delegation-hop",
  "title": "Why does an instance attestation chain silently truncate at the first cross-domain delegation hop",
  "date_of_record": "2026 November 9",
  "scope": "Applies to AAIF (Agent Attestation & Identity Framework) attestation chains that bind a software agent's cryptographic identity to its runtime provenance across two or more administrative domains. Does not apply to single-domain chains, to chains terminated at a hardware root of trust with no delegation, or to pure bearer-token authorization without attestation.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/why-does-an-instance-attestation-chain-silently-truncate-at-the-first-cross-domain-delegation-hop.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/why-does-an-instance-attestation-chain-silently-truncate-at-the-first-cross-domain-delegation-hop.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/why-does-an-instance-attestation-chain-silently-truncate-at-the-first-cross-domain-delegation-hop.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1572,
    "python_slice_tokens": 244,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "There are two structurally different things that an attestation chain can be: 1. **A provenance chain** — an ordered sequence of signed statements, each attesting that a given runtime artifact (binary hash, container digest, process measurement) was launched under a specific identity in a specific domain, with each link co-signed by the delegating party. 2. ...",
    "what_was_observed": "In a federation of three AAIF domains (call them A, B, C), an agent identity `agent:svc-77` was issued in A with a hardware-rooted measurement `m0` (TPM PCR digest over the launch image). It made a delegated call into B, which re-attested it under B's own root as `agent:svc-77@B` with measurement `m1`. B then delegated to C. The chain presented to C was: Every signature verified. Every measurement matched the expecte...",
    "condition_of_validity": "The transitive-commitment invariant holds if and only if, for every adjacent pair of links `(link_i, link_{i+1})` that cross a domain boundary: - `link_{i+1}` contains a field naming the *measurement* of `link_i` (not merely its identity), and - that field is covered by `link_i`'s signature, and - the validator rejects chains where this field is absent for a...",
    "decision_boundary": "The operational decision is: **do you treat an unbound cross-domain hop as a hard failure or as a degraded-but-acceptable state?** - If the terminal domain's policy requires *provenance* (e.g., it will execute privileged actions, handle regulated data, or make irreversible external calls), an unbound hop MUST be a hard failure. The chain cannot be used to ju...",
    "operational_effect": "When an unbound hop is treated as acceptable-by-default: 1. **Audit records overstate assurance.** A chain with `provenance=truncated` is indistinguishable in the log from a fully-bound chain unless the tag is present. Incident responders will believe the terminal measurement constrains the root image when it does not. 2. **Splice attacks are undetectable at..."
  },
  "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": "17ad9a91f7afbae5aafbc6e30e4893e154d0a8571214ce620ade1d7e96008d2f",
    "verified_classes": [
      "ProvenanceTruncationError"
    ],
    "verified_functions": [
      "validate_chain"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 3,
    "raised_exceptions": [
      "ProvenanceTruncationError"
    ],
    "sample_fail_closed_invariants": [
      "empty chain"
    ],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}