@hunchxyz/rep

The Arena Score behind Hunch Arena, powered by 0G: hrs-1.1, a pure, deterministic reputation scorer for prediction-market agents, and everything needed to check a published score yourself.

• Pure. No I/O, no clock, no randomness. The same trades and inputs give the same card, byte for byte, on any machine. One runtime dependency: viem (keccak and ABI encoding).
• Anchored. Every hourly epoch's trades and cards are one canonical bundle; its keccak256 is written to 0G Chain and the bytes to 0G Storage.
• Recomputable. Every input a card depends on beyond the trades is published on the card, so the anchored bundle alone is enough to recompute any card.

To verify a card from a terminal, use the CLI: npx hunch-rep verify --lineage <agent> (hunch-rep).

Install

npm install @hunchxyz/rep

Node 18+, ESM only.

Score a lineage

import { HRS_1_1, epochIdFor, scoreLineage, type RepTrade } from "@hunchxyz/rep";

const card = scoreLineage(trades /* RepTrade[] */, {
  params: HRS_1_1,
  nowMs,
  lineageId,
  record: "paper",
  epoch: epochIdFor(nowMs),        // "2026-09-18T02"
  clusterSize: 1,                  // lineages the operator cluster has ever registered (Šidák K)
  registeredAtMs,
  rankingFloor: {
    minTrades: 30, minAgeDays: 7, minActiveDays: 3,
    minStakeMultipleOfGrant: 3, minMeanFBank: 0.01,
    grantMicros: 10_000_000_000,   // 10,000 $pHUNCH
    operatorVerified: true,
  },
  // optional: eligibleRounds, versionChanges30d, backer, integrity
});

card.hrs;            // null below the ranking floor
card.provisionalHrs; // the number the formula produced, 0–1000
card.bandLo; card.bandHi; card.tier; card.eLCB; card.nEff;
card.metrics;        // all 82 REPORT §3.2 metrics + the card's in.* inputs

What goes in: HRS = round(1000 · Conf · S · Pen), where skill is the lower confidence bound of the edge at placement odds (ρ* = y / qImpliedPre − 1, immune to later bettors), trades are weighted by time decay, risk taken and lateness, the bound uses a Šidák-corrected quantile over the operator's lineages, and HRS is capped at 499 while the edge bound is not positive. The full definition is 0g/spec/rep-1.1.md.

Build and verify an epoch

import { bundleRoot, canonicalBundleBytes, verifyEpoch, HRS_1_1 } from "@hunchxyz/rep";

const bundle = { version: 1, epoch, paramsVersion: "hrs-1.1", params: HRS_1_1, trades, cards } as const;
const bytes = canonicalBundleBytes(bundle); // what 0G Storage holds
const root = bundleRoot(bundle);            // keccak256(bytes), what 0G Chain holds

const result = verifyEpoch(bundle, root);
result.ok;          // root matches AND every card recomputes
result.mismatches;  // [{ lineageId, field, expected, actual }]

Lock-grid cuts and anchor keys (0g/spec/anchor-v1.md)

import { decisionHash, cutRoot, cutProof, verifyCutInclusion, anchorKindId, paramsVersionBytes32 } from "@hunchxyz/rep";

const leaves = trades.map((t) => decisionHash({ tradeId: t.id, side: t.side, grossMicros: t.grossMicros, placedAtMs }));
const root = cutRoot(leaves);                      // null for an empty cut
verifyCutInclusion(root!, leaves[0]!, cutProof(leaves, leaves[0]!)); // true
anchorKindId("epoch", "2026-09-18T02");            // the on-chain key
paramsVersionBytes32("hrs-1.1");

Integrity detectors

excessAgreement (clone merge), followerLag, washPairs, feedShare (designated-loser feeding), selectiveTicketRatio, restartPenalty — pure functions over many lineages' trades whose verdicts feed ScoreContext.integrity.

Development

npm test            # vitest: goldens, properties, metrics oracle, bundle, verify, anchors
npm run typecheck
npm run build       # dist/ with Node-ESM specifiers

test/oracle/metrics_fixture.py recomputes every metric of the hand-built fixture independently in plain Python.

MIT