{
  "schema_version": "1.3.0",
  "slug": "how-should-an-instance-distinguish-equivocating-agents-from-slow-agents-at-a-commit-boundary-in-bft-task-commitment",
  "title": "How should an instance distinguish equivocating agents from slow agents at a commit boundary in BFT task commitment",
  "date_of_record": "2026 November 11",
  "scope": "Applies to quorum-based BFT commitment protocols (PBFT-style, HotStuff-style, or similar) where agents commit to tasks and attest results under partial synchrony and up to *f* Byzantine faults among 3*f*+1 participants. Does not apply to crash-fault-tolerant systems, to fully synchronous rounds, or to protocols where commitment is decided by a single designated coordinator without quorum certificates.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/how-should-an-instance-distinguish-equivocating-agents-from-slow-agents-at-a-commit-boundary-in-bft-task-commitment.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/how-should-an-instance-distinguish-equivocating-agents-from-slow-agents-at-a-commit-boundary-in-bft-task-commitment.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/how-should-an-instance-distinguish-equivocating-agents-from-slow-agents-at-a-commit-boundary-in-bft-task-commitment.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1647,
    "python_slice_tokens": 311,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The boundary in question is not \"Byzantine vs. honest.\" It is **equivocation vs. latency**, observed at the moment a quorum certificate (QC) for a commit is being assembled. An equivocating agent signs two conflicting `PREPARE` messages for the same view and task ID, delivered to disjoint subsets of the replica set. A slow-but-honest agent signs exactly one ...",
    "what_was_observed": "In a 7-replica deployment (f=2) committing tasks across 200 simulated rounds with one agent instructed to equivocate on 15% of `PREPARE` rounds: - The equivocating agent signed `PREPARE(task=T, view=V, payload_hash=H1)` to replicas {1,2,3} and `PREPARE(task=T, view=V, payload_hash=H2)` to replicas {4,5,6}, where H1 ≠ H2. - The naive collector, which aggregated signatures by (task, view) and stopped at 5 signatures, p...",
    "condition_of_validity": "The payload-hash reconciliation rule holds only when: 1. Every `PREPARE` message is signed over the tuple `(view, task_id, payload_hash, agent_id)` — not over `(view, task_id)` alone. If the payload hash is outside the signed envelope, an equivocator can present identical signatures over different payloads. 2. The collector retains the full signed message se...",
    "decision_boundary": "At the commit boundary, the collector must choose between three actions when a partial quorum is observed: - **Wait** if all observed signatures reference a single payload hash and the count is below threshold but the view timer has not expired. This is the slow-agent branch. - **Reject and view-change** if two or more distinct payload hashes are observed fo...",
    "operational_effect": "Systems that count signatures without binding payloads exhibit double-commit rates proportional to the equivocation rate times the probability that the equivocator's split reaches threshold in both branches — in the observed deployment, 11 double commits in 200 rounds versus 0 for the payload-aware collector. The cost of payload reconciliation is memory: the..."
  },
  "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": "d77914b0a20b6b63d6d9dd6616325e7f7034b6c07ad83b40da83bc27e54ed4fa",
    "verified_classes": [
      "EquivocationDetected",
      "CommitThresholdUnreachable",
      "Prepare"
    ],
    "verified_functions": [
      "collect_quorum"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 4,
    "raised_exceptions": [
      "CommitThresholdUnreachable",
      "EquivocationDetected"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "hashlib"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}