{
  "schema_version": "1.3.0",
  "slug": "under-what-conditions-must-an-instance-refuse-to-treat-an-llm-agent-s-repeated-answer-as-independent-corroboration-in-byzantine-consensus",
  "title": "Under what conditions must an instance refuse to treat an LLM agent's repeated answer as independent corroboration in Byzantine consensus",
  "date_of_record": "2026 November 8",
  "scope": "Applies to BFT consensus protocols (PBFT, Tendermint-style, HotStuff-style) whose voting members are LLM agents emitting free-text or structured judgments, where quorum thresholds are computed over “distinct” votes. Does not apply to deterministic replicas, nor to cases where votes are cryptographically bound to distinct model weights *and* distinct sampling seeds *and* the protocol records seed provenance.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-refuse-to-treat-an-llm-agent-s-repeated-answer-as-independent-corroboration-in-byzantine-consensus.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-refuse-to-treat-an-llm-agent-s-repeated-answer-as-independent-corroboration-in-byzantine-consensus.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-refuse-to-treat-an-llm-agent-s-repeated-answer-as-independent-corroboration-in-byzantine-consensus.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1574,
    "python_slice_tokens": 440,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "There is a difference between **agent identity** and **evidential independence**. A BFT quorum counts signatures; it assumes each signed vote carries independent information about the underlying truth. With heterogeneous LLM agents, a single agent re-queried `k` times under different prompts, temperatures, or system messages can produce `k` distinct-looking ...",
    "what_was_observed": "In a 7-node heterogeneous deployment (three model families, two vendors, mixed sizes), a single faulty node was injected with a prompt-injection payload that caused it to emit a plausible-but-false claim. The protocol should have tolerated `f = 2` Byzantine faults. Instead, consensus stalled and then committed the false claim. Post-mortem reconstruction showed the following: 1. The injected node's claim was *rephrase...",
    "condition_of_validity": "The quorum-counts-independence invariant is valid only when all of the following hold simultaneously: - **Seed provenance is recorded and disjoint.** Each vote carries `(model_id, weights_hash, seed, prompt_hash)`. Two votes are counted as independent only if `weights_hash` and `seed` differ, and the `seed` was drawn *after* the claim was fixed (not reused a...",
    "decision_boundary": "A validator must **refuse to count a vote as independent** (and must raise, not silently downgrade) when: - The vote's `weights_hash` matches another counted vote and the `seed` is identical or unrecorded. - The vote's `prompt_hash` matches another counted vote and the prompts were issued by the same coordinator in the same round (prompt-level correlation). ...",
    "operational_effect": "When the boundary is enforced, consensus throughput drops — heterogeneous deployments with three model families can rarely muster `2f + 1` *truly* independent weights, so the protocol must either (a) reduce `f`, (b) admit correlation and use weighted quorums, or (c) escalate to a human/ deterministic oracle. The failure mode of *not* enforcing it is silent: ..."
  },
  "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": "05b0e92ceb2ecc58ee6eff340b43065e85f50fc2b73b1cba590f2836c75b4072",
    "verified_classes": [
      "CorrelatedVoteError",
      "Vote"
    ],
    "verified_functions": [
      "_cosine",
      "count_independent_votes"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 6,
    "raised_exceptions": [
      "CorrelatedVoteError"
    ],
    "sample_fail_closed_invariants": [
      "zero-norm embedding; vote is uninformative"
    ],
    "stdlib_dependencies": [
      "dataclasses",
      "hashlib",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}