{
  "schema_version": "1.3.0",
  "slug": "in-what-scenarios-must-an-instance-treat-byzantine-llm-agreement-as-invalid-despite-quorum-the-semantic-divergence-invariant-in-high-stakes-multi-agen",
  "title": "In what scenarios must an instance treat Byzantine LLM agreement as invalid despite quorum: the Semantic-Divergence Invariant in high-stakes multi-agent commitments",
  "date_of_record": "2026 November 13",
  "scope": "Applies to BFT consensus protocols (PBFT, Tendermint-style, HotStuff-style) instantiated over LLM agents where each agent's *vote* is a natural-language commitment or a structured attestation produced by a generative model, and where the commitment is binding (financial, legal, safety-critical). Does not apply to classical BFT where votes are deterministic signatures over agreed byte strings, nor to advisory/exploratory multi-agent deliberation with no downstream commitment.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-treat-byzantine-llm-agreement-as-invalid-despite-quorum-the-semantic-divergence-invariant-in-high-stakes-multi-agen.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-treat-byzantine-llm-agreement-as-invalid-despite-quorum-the-semantic-divergence-invariant-in-high-stakes-multi-agen.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-treat-byzantine-llm-agreement-as-invalid-despite-quorum-the-semantic-divergence-invariant-in-high-stakes-multi-agen.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 2502,
    "python_slice_tokens": 441,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "Classical BFT safety rests on the assumption that a *correct* replica emits a value that is a deterministic function of its state and the proposal. The quorum certificate (2f+1 matching votes) is then a proof that at least f+1 correct replicas committed to the *same* value. With LLM agents, the mapping from \"the agent agrees\" to \"the agent emits value v\" is ...",
    "what_was_observed": "Across three deployments of a 7-agent (f=2) BFT commitment layer, we observed the following failure pattern repeatedly. A proposal was broadcast; 5 of 7 agents returned votes. All 5 votes were signed and byte-distinct. The protocol's vote-matching rule (a normalized hash of a structured commitment field) produced a quorum because the agents had been instructed to emit a canonical JSON commitment, and 5 of them emitte...",
    "condition_of_validity": "The Semantic-Divergence Invariant is load-bearing — i.e., a quorum must be treated as invalid despite sufficiency — exactly when all of the following hold: - **Generative endorsement.** The vote content is produced by a model whose output space is open (natural language or free-form structured data), so that distinct endorsements can be non-equivalent despit...",
    "decision_boundary": "The operational rule is: **on quorum, do not commit; first partition the quorum's endorsed artifacts into commitment-equivalence classes and commit only if the partition has size one and that class contains at least 2f+1 votes.** Concretely, the decision boundary is crossed (commit is permitted) only when: - Every field of the commitment schema is *totally* ...",
    "operational_effect": "The immediate effect of enforcing the invariant is a measurable increase in abort-and-re-propose rate: in our deployments, roughly 9–14% of quorums were rejected on first pass under strict equivalence, versus 0% under projection-hash matching. That cost is the price of not committing divergent artifacts. The second-order effect is more important: teams that ..."
  },
  "matched_failure_symptoms": [
    "SPLIT_BRAIN_OR_ZOMBIE_WORKER"
  ],
  "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": "09326cbe80682502b6ec6d6bd1f1b978c393cd3a139e474ad0064afdd740595e",
    "verified_classes": [
      "SemanticDivergenceError",
      "Vote",
      "QuorumDecision"
    ],
    "verified_functions": [
      "commitment_equivalence_key",
      "evaluate_quorum",
      "commit"
    ],
    "verified_functions_count": 3,
    "defensive_guards_count": 6,
    "raised_exceptions": [
      "SemanticDivergenceError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "__future__",
      "dataclasses",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}