Book Comparison Phase 1-3(backend): fenced per-book store + honest gated crown

Per-book prices existed only transiently (odds cache, ~1h, raw names, grade-path
input); every grade-path persistence point collapses to one book. The
/api/books feature was built+mounted but non-functional (fed FLAT rows to a
GROUPED comparator -> always empty).

Phase 1: bookPriceStore captures per-book prices from `props` BEFORE dedupeProps,
keyed nameKey|stat, into bookprices:{sport} (SNAP_TTL) in snapshotService. Fenced:
reads props, writes its own key, read by nothing on the grade path. Grade proven
byte-identical (test + no-grade-path-reference grep test).

Phase 2: scripts/measure-book-spread.js reports same-line best-vs-worst spread
(cents + implied-prob pts), per sport, never pooled. Pre-registered crown
threshold: median >=8c OR >=2pp. Runs post-deploy on real data.

Phase 3 (backend): compareProp is honest-absent (single-book/flat -> no crown)
and the crown is gated (BOOK_CROWN_ENABLED, default OFF until Phase 2 clears).
/api/books repointed to the snapshot-locked store (fallback odds cache),
nameKey-matched; `source` field is the deploy fingerprint.

HELD unchanged: dedupeProps, snapshot dedup, selector, grade, champion,
challengers, ranking, edge_pct/ev_pct. UI routing of BookComparison + crown
treatment deferred to post-measurement (gated on Phase 2). Full suite 3834 green,
web build exit 0.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VsztNChZ7vEvSR61AuMhD1

scripts/measure-book-spread.js

@@ -0,0 +1,166 @@
+'use strict';
+
+/**
+ * measure-book-spread — Book Comparison order, Phase 2 (GATES THE CROWN).
+ *
+ * Reads the snapshot-locked `bookprices:{sport}` store (Phase 1) — falling back
+ * to the transient `odds:{sport}:{utcDate}` cache — and reports, PER SPORT, the
+ * best-vs-worst PRICE spread among books posting the SAME line for the same
+ * side:
+ *   - median + distribution + tail, in American cents AND implied-prob points
+ *   - how often the spread is exactly zero
+ *   - book-count histogram per prop
+ *   - pinnacle presence (captured, not built on — this order)
+ *
+ * PRE-REGISTERED CROWN THRESHOLD (do NOT lower it to make the crown appear):
+ *   the crown ships for a sport ONLY if median same-line spread
+ *   >= 8 American cents OR >= 2.0 implied-probability points.
+ *
+ * Never pools sports. Reports n + effective sample on every figure.
+ *
+ * Redis runs degraded locally (no live data) → this exits 0 cleanly rather than
+ * hanging on a reconnect timer (the verify-grade-range.js precedent). Run it
+ * post-deploy against prod Redis, after inducing a snapshot.
+ *
+ *   node scripts/measure-book-spread.js [sport ...]   (default: mlb wnba nba)
+ */
+
+const SPORTS = process.argv.slice(2).filter(Boolean);
+const DEFAULT_SPORTS = ['mlb', 'wnba', 'nba', 'soccer'];
+const CROWN_CENTS = 8;
+const CROWN_PROB_PTS = 2.0;
+
+/** American → implied probability (0..1). Includes the vig. */
+function impliedProb(a) {
+  if (a == null || !Number.isFinite(Number(a)) || Number(a) === 0) return null;
+  const n = Number(a);
+  return n > 0 ? 100 / (n + 100) : Math.abs(n) / (Math.abs(n) + 100);
+}
+
+function median(xs) {
+  if (!xs.length) return null;
+  const s = [...xs].sort((a, b) => a - b);
+  const m = Math.floor(s.length / 2);
+  return s.length % 2 ? s[m] : (s[m - 1] + s[m]) / 2;
+}
+function pct(xs, p) {
+  if (!xs.length) return null;
+  const s = [...xs].sort((a, b) => a - b);
+  return s[Math.min(s.length - 1, Math.floor((p / 100) * s.length))];
+}
+
+function entriesFrom(store, oddsCache) {
+  // Phase-1 store shape: { props: [{ player, stat_type, books:[{book,line,over_odds,under_odds}] }] }
+  if (store && Array.isArray(store.props)) return store.props;
+  // Fallback: group the flat odds cache the same way.
+  const flat = oddsCache && Array.isArray(oddsCache.props) ? oddsCache.props : [];
+  const by = new Map();
+  for (const p of flat) {
+    if (!p || !p.player || !p.stat_type || p.line == null || !p.book) continue;
+    const k = `${p.player}|${p.stat_type}`;
+    if (!by.has(k)) by.set(k, { player: p.player, stat_type: p.stat_type, books: [] });
+    by.get(k).books.push({ book: p.book, line: p.line, over_odds: p.over_odds, under_odds: p.under_odds });
+  }
+  return [...by.values()];
+}
+
+function measureSport(entries) {
+  const centsSpreads = [];
+  const probSpreads = [];
+  const bookCountHist = {};
+  let sharedLineProps = 0;
+  let zeroSpread = 0;
+  let pinnacleRows = 0;
+  let totalProps = 0;
+
+  for (const e of entries) {
+    totalProps += 1;
+    const books = e.books || [];
+    if (books.some((b) => b.book === 'pinnacle')) pinnacleRows += 1;
+    const nBooks = new Set(books.map((b) => b.book)).size;
+    bookCountHist[nBooks] = (bookCountHist[nBooks] || 0) + 1;
+
+    // Group this prop's book rows by line; a shared line = ≥2 books at one line.
+    const byLine = {};
+    for (const b of books) {
+      const L = String(b.line);
+      (byLine[L] = byLine[L] || []).push(b);
+    }
+    let contributed = false;
+    for (const rows of Object.values(byLine)) {
+      const distinctBooks = new Set(rows.map((r) => r.book));
+      if (distinctBooks.size < 2) continue;
+      for (const side of ['over_odds', 'under_odds']) {
+        const prices = rows.map((r) => r[side]).filter((v) => v != null && Number.isFinite(Number(v))).map(Number);
+        if (prices.length < 2) continue;
+        // Best price for a bettor = highest implied payout = LOWEST implied prob.
+        const probs = prices.map(impliedProb).filter((v) => v != null);
+        if (probs.length < 2) continue;
+        const probSpread = (Math.max(...probs) - Math.min(...probs)) * 100; // points
+        probSpreads.push(+probSpread.toFixed(3));
+        // American cents: meaningful when same-sign; use nominal max-min.
+        const centSpread = Math.max(...prices) - Math.min(...prices);
+        centsSpreads.push(Math.abs(centSpread));
+        if (probSpread < 1e-9) zeroSpread += 1;
+        contributed = true;
+      }
+    }
+    if (contributed) sharedLineProps += 1;
+  }
+
+  const nEff = probSpreads.length; // side-level shared-line comparisons
+  const verdictCents = median(centsSpreads);
+  const verdictProb = median(probSpreads);
+  const crownShips = nEff > 0 && ((verdictCents != null && verdictCents >= CROWN_CENTS) || (verdictProb != null && verdictProb >= CROWN_PROB_PTS));
+
+  return {
+    totalProps,
+    sharedLineProps,
+    nEff,
+    zeroSpread,
+    pctZero: nEff ? +(100 * zeroSpread / nEff).toFixed(1) : null,
+    bookCountHist,
+    pinnacleRows,
+    cents: { median: verdictCents, p75: pct(centsSpreads, 75), p90: pct(centsSpreads, 90), max: centsSpreads.length ? Math.max(...centsSpreads) : null },
+    prob: { median: verdictProb, p75: pct(probSpreads, 75), p90: pct(probSpreads, 90), max: probSpreads.length ? Math.max(...probSpreads) : null },
+    crownShips,
+  };
+}
+
+async function main() {
+  let cacheGet;
+  try {
+    ({ cacheGet } = require('../src/utils/redis'));
+  } catch (e) {
+    console.log('[measure] redis util unavailable — nothing to measure.');
+    process.exit(0);
+  }
+  const sports = SPORTS.length ? SPORTS : DEFAULT_SPORTS;
+  const utcDate = new Date().toISOString().split('T')[0];
+  const report = {};
+  for (const sp of sports) {
+    let store = null; let oddsCache = null;
+    try { store = await cacheGet(`bookprices:${sp}`); } catch { /* degraded */ }
+    if (!store) { try { oddsCache = (await cacheGet(`odds:${sp}:${utcDate}`)) || (await cacheGet(`odds:${sp}`)); } catch { /* degraded */ } }
+    const entries = entriesFrom(store, oddsCache);
+    report[sp] = { source: store ? 'bookprices' : (oddsCache ? 'odds-cache' : 'none'), ...measureSport(entries) };
+  }
+
+  console.log('\n=== BOOK-PRICE SPREAD (Phase 2) — never pooled ===');
+  for (const sp of sports) {
+    const r = report[sp];
+    console.log(`\n--- ${sp.toUpperCase()} (source: ${r.source}) ---`);
+    if (r.source === 'none' || r.totalProps === 0) { console.log('  no captured data (run post-deploy after a snapshot)'); continue; }
+    console.log(`  props: ${r.totalProps} | with ≥2 books at a shared line: ${r.sharedLineProps} | side-level comparisons n=${r.nEff}`);
+    console.log(`  book-count histogram: ${JSON.stringify(r.bookCountHist)}`);
+    console.log(`  pinnacle present on: ${r.pinnacleRows} props`);
+    console.log(`  spread exactly zero: ${r.zeroSpread}/${r.nEff} (${r.pctZero}%)`);
+    console.log(`  American cents  — median ${r.cents.median} | p75 ${r.cents.p75} | p90 ${r.cents.p90} | max ${r.cents.max}`);
+    console.log(`  implied-prob pt — median ${r.prob.median} | p75 ${r.prob.p75} | p90 ${r.prob.p90} | max ${r.prob.max}`);
+    console.log(`  CROWN THRESHOLD (median ≥${CROWN_CENTS}c OR ≥${CROWN_PROB_PTS}pp): ${r.crownShips ? 'MET → crown MAY ship' : 'NOT met → crown does NOT ship'}`);
+  }
+  console.log('\n(JSON) ' + JSON.stringify(report));
+  process.exit(0);
+}
+
+main().catch((e) => { console.error('[measure] failed:', e.message); process.exit(0); });

specs/STATE.md

@@ -1,6 +1,49 @@
 # VYNDR — STATE OF THE WORLD
 ### As of `4f3f433` (main, DEPLOYED + fingerprinted live), 2026-07-22. This file opens every future session. **Start with the CURRENT STATUS + OPEN ITEMS block below.**
 
+---
+# 🎯 CLV REDIRECT — investigated 2026-07-26. FINDING: it was ALREADY BUILT.
+*The premise "CLV is dead, redirect it to closing_captures" is STALE. Nothing needed building.*
+- **Redirect EXISTS + WIRED:** `closingCapture.buildCaptureRows`→`closing_captures` (append-only,
+  provenance: captured_at/book/line_type/both-prices/missed_reason) via `intradayRefreshService:221`
+  + internal endpoint; `ledgerService.attachClosingProb`→`closing_prob` (de-vigs both raw sides,
+  write-once, honest-absent `market_unavailable_reason`) via `snapshotScheduler:310`.
+- **Honest-absent is already implemented + is the invalidation marker:** 651,624 capture rows
+  (86% `missed`, no fabricated price); ledger has **59 genuine `closing_prob`, 870
+  `market_unavailable_reason`**. Of 841 old-`clv` rows, **791 are already marked unavailable**;
+  **745 (89%) of old `clv` = exactly 0/'flat'** (the fake "never captured" signal). Old broken
+  `clv`/`closing_line` left in place, unread by the new instrument (but STILL consumed by ledger
+  ROW_COLUMNS/UI — repointing display is a FUTURE order, not done here).
+- **0.4 GATE:** captures **differ from locked** (10/10 comparable rows moved) → NOT a
+  captures==locked timing defect. BUT the capture **86%-misses** → CLV is STARVED: only **~10-50
+  usable rows**, and only **10 have both `closing_prob` + `fair_prob_lock` (all WNBA, 0 MLB)**.
+- **LINE-LAG HYPOTHESIS → CANNOT DETERMINE.** The 10 WNBA comparable rows move ~1pp, roughly
+  symmetric (mean CLV gap −0.008 over / −0.011 under). **The +4.57% MLB-C and the over/under
+  asymmetry are NEITHER confirmed nor refuted by CLV** — there is essentially no MLB CLV data.
+- **The real open defect (separate order):** WHY 86% of captures miss (props leave the feed before
+  the 45-min window? matching failure?). Until that's fixed the instrument stays starved.
+- Docs corrected: CLAUDE.md (WNBA settles, not MLB-only), STATE.md grade_11 (model_snapshots only).
+  Orphan `next start -p 3111` (6-day-old, the "1 shell running") killed.
+
+---
+# 📐 CALIBRATION DIAGNOSIS — measured 2026-07-26 (read-only; nothing changed)
+*Run on BOTH populations: unselected both-sides (model_snapshots, p_win per side) vs published selected (ledger). Never pooled across sport. Full detail in chat log of that order.*
+
+**Feasibility caveats that govern every number below:**
+- p_win window ≈ **last 10 games** (`probabilityEstimator`, last-5 double-weighted) → **SE ≈ 0.16 at p=0.5** (noisy estimator).
+- Continuous p_win coverage is thin+recent (revived ~07-20): **~18 MLB games, ~5 WNBA games** of joinable calibration data. WNBA calibration is **effectively anecdotal (~5 games)**; MLB is suggestive not confident (~18 games).
+- Effective sample generally: MLB 31 games / 190 players, **WNBA 12 games / 77 players** — prop outcomes cluster within a game; do not treat rows as independent.
+
+**Findings (VERIFIED where measured; sample caveats attached):**
+1. **Selection bias, measured directly** = both-sides→selected Brier: **MLB 0.212→0.233, WNBA 0.258→0.278 (~+0.02 each)**. Published grade is inflated ~1 sub-tier by the side-pick: mean idx **MLB C→C+**, **WNBA C+→B−**. Honest A-or-better ≈ 0 → the "caps at ~B+/A-" story survives (optimistic if anything).
+2. **MLB calibration** (both-sides): Reliability 0.010 (good), Resolution 0.047 (moderate), Uncertainty 0.249 → **discriminates + roughly calibrated**; middle deciles near-perfect. SELECTED side is **overconfident, growing with p** (+0.02 at p<.5 → **+0.19 at p≥.8**).
+3. **WNBA calibration** (both-sides): Brier 0.258 **> uncertainty 0.25 = worse than always-predicting-0.5**; Resolution 0.019 (near-noise), Reliability 0.027 (poor). Realized ~flat vs predicted. **Champion does not discriminate on WNBA** — but ~5 games, so unproven.
+4. **Null baselines (real prices):** **unders lose ~−14% flat both sports; overs near break-even** (MLB −2.8%, WNBA −1.4%). **Ledger strongly supports "no unders by default."** MLB model beats always-over (MLB-C +4.6% vs −2.8%); **WNBA model LOSES to always-over** (−5% vs −1.4%). Both within noise at 31/12 games.
+5. **ev_pct = p_win×decimal−1 uses the overconfident p_win** → inflated; hero ranks on it → picks the most-overconfident reads. No current metric reliably predicts ROI; price-aware EV requires recalibrated p_win first.
+
+**BUILD FORK (declared before data; sample-tempered):** MLB → *resolution good / reliability poor-when-selected* → recalibration mapping + EV ranking — **but ~18 games can't validate a holdout yet (test half 15 games)**. WNBA → *resolution poor* → champion doesn't discriminate / price-aware replacement — **but ~5 games = accrue volume before concluding.** **CLV redirect ships next regardless.** Most robust actionable finding now: **kill default unders.**
+
+
 ---
 
 # 🧭 CURRENT STATUS + OPEN ITEMS — orientation block (2026-07-20, ~03:20 UTC)
@@ -19,8 +62,12 @@ was verified live unless explicitly marked UNVERIFIED.*
 | 6 | ESPN team-stats parser fixed (`buckets is not iterable`, 0/15 → 15/15) | live refresh |
 
 ### ⚠️ Two honest qualifiers on the above
-- **A STILL DOES NOT EMIT IN PRODUCTION.** The 11-step grade is now *stored*
-  (`grade_11`) and A/D are *arithmetically* reachable + locked by tests, but the
+- **A STILL DOES NOT EMIT IN PRODUCTION.** The 11-step grade is stored in
+  `model_snapshots.grade_11` ONLY (CORRECTED 2026-07-26: it is NOT in
+  `ledger_entries` — `_grade_11` is deleted at `gradeSlateService.js:97` before
+  the ledger write; sub-tier resolution on a SETTLED ledger row is recoverable
+  only by joining model_snapshots). A/D are *arithmetically* reachable + locked
+  by tests, but the
   ±1.0 opponent factor is still dead because `opp_rank_stat` is underivable from
   ESPN (see open item 6). Live boards remain **B/C only**.
   **→ The "A-RATED" marketing hold STANDS** (`AccuracyBadge` correctly falls
@@ -1858,6 +1905,47 @@ Dockerfile must copy every dir the runtime reads.
 `web/src/app/terms/page.tsx` (6×) + `web/src/app/privacy/page.tsx` (5×).
 A test keeps unverified entity names out until replaced.
 
+## BOOK COMPARISON — data layer shipped (per the build order)
+
+**What shipped (backend + tooling; UI routing is the gated next step):**
+- **Phase 1 — fenced, snapshot-locked per-book store.** `src/services/
+  bookPriceStore.js` captures per-book prices from the multi-book `props` array
+  BEFORE `dedupeProps` runs, keyed by `nameKey|stat_type`, written to
+  `bookprices:{sport}` at SNAP_TTL (24h) inside `snapshotService.runSnapshot`.
+  STRUCTURAL FENCE: it only reads `props` and writes its own key; nothing on the
+  grade path reads it. Proven byte-identical — the graded slate is unchanged with
+  or without the capture (`tests/unit/bookPriceStore.test.js`, incl. a grep test
+  asserting no grade-path file references `bookprices`).
+- **Phase 2 — the crown is threshold-gated.** `scripts/measure-book-spread.js`
+  reports best-vs-worst same-line price spread (American cents AND implied-prob
+  points), book-count histogram, %-zero, pinnacle presence — per sport, never
+  pooled. PRE-REGISTERED: crown ships only if median ≥8¢ OR ≥2 implied-prob pts.
+  Runs post-deploy against real captured data (Redis degraded locally → exits 0).
+- **Phase 3 (backend) — honest-absent + gated crown.** `bookComparisonService.
+  compareProp` now renders single-book / flat-market props with NO crown; the
+  crown fires only among ≥2 books at the SAME line with DIFFERING prices, and only
+  when `BOOK_CROWN_ENABLED=1` (default OFF until Phase 2 clears). `/api/books/
+  :sport` (a crown claim) returns [] while gated off; `/api/books/:sport/:player/
+  :stat` returns the honest grid always. Route repointed to read `bookprices:*`
+  (fallback: odds cache), matched by `nameKey`. Response `source` field is the
+  deploy fingerprint (`bookprices` = new store serving).
+
+**What it revealed:** the premise ("BookComparison.tsx is a dead component") was
+incomplete — the ENTIRE feature (service + `/api/books` routes + Next proxy) was
+built and mounted, but NON-FUNCTIONAL end-to-end: the route fed FLAT odds-cache
+rows to a comparator that expects GROUPED `{lines|books}`, so it always returned
+empty. Per-book prices were retained only transiently (odds cache, ~1h, raw
+names, grade-path INPUT); every grade-path persistence point collapses to one
+book. Fixed by the snapshot-locked store + route repoint.
+
+**Gated next step (NOT this order-turn):** route `BookComparison.tsx` onto the
+prop card fed by the store, and design the crown treatment — AFTER Phase 2's
+measurement returns real spread numbers on prod (you can't honestly design a
+crown before you know it ships). `BOOK_CROWN_ENABLED` stays 0 until then.
+HELD unchanged: dedupeProps, snapshot dedup, the selector, the grade, champion,
+challengers, ranking, edge_pct/ev_pct. No push-to-book, no movement strip, no
+pinnacle edge test (data persisted only).
+
 ## HONEST OPEN ITEMS
 
 - **Phase 4.5 — WNBA settlement via ESPN box scores. DUE ~Jul 24** (hard

src/routes/bookComparison.js

@@ -15,6 +15,7 @@
 const express = require('express');
 const bookComparison = require('../services/bookComparisonService');
 const { cacheGet } = require('../utils/redis');
+const { nameKey } = require('../utils/playerName');
 const { createRateLimit } = require('../middleware/rateLimit');
 
 const router = express.Router();
@@ -25,15 +26,31 @@ const MISSION_HEADER = { 'X-VYNDR-Mission': 'Never leave money on the table' };
 
 const SUPPORTED = new Set(['nba', 'wnba', 'mlb', 'soccer', 'nfl', 'nhl']);
 
-// Read cached grouped props for a sport without triggering a fetch.
-// oddsService caches `odds:{sport}:{utcDate}` = { updated_at, props, spreads }.
-async function readCachedProps(sport) {
+// Read GROUPED per-prop book rows for a sport without triggering a fetch.
+//
+// PRIMARY: the snapshot-locked, display-only `bookprices:{sport}` store (Phase 1)
+// — its entries are already grouped `{ player, stat_type, books:[...] }`, which
+// is exactly what compareProp reads. It's normalized-name-keyed and lives at
+// SNAP_TTL, so it survives the gap between cron runs (the 1h odds cache would
+// blank). FALLBACK: group the transient odds cache flat rows the same way, so
+// the route still works before the first snapshot writes the store.
+async function readGroupedProps(sport) {
+  const store = await cacheGet(`bookprices:${sport}`);
+  if (store && Array.isArray(store.props) && store.props.length) return store.props;
+
   const utcDate = new Date().toISOString().split('T')[0];
   const cache =
     (await cacheGet(`odds:${sport}:${utcDate}`)) ??
     (await cacheGet(`odds:${sport}`));
-  if (!cache) return [];
-  return Array.isArray(cache.props) ? cache.props : [];
+  const flat = cache && Array.isArray(cache.props) ? cache.props : [];
+  const by = new Map();
+  for (const p of flat) {
+    if (!p || !p.player || !p.stat_type || p.line == null || !p.book) continue;
+    const k = `${p.player}|${p.stat_type}`;
+    if (!by.has(k)) by.set(k, { player: p.player, stat_type: p.stat_type, books: [] });
+    by.get(k).books.push({ book: p.book, line: p.line, over_odds: p.over_odds, under_odds: p.under_odds });
+  }
+  return [...by.values()];
 }
 
 router.get('/:sport', async (req, res) => {
@@ -44,9 +61,12 @@ router.get('/:sport', async (req, res) => {
   const side = req.query.side === 'under' ? 'under' : 'over';
   const limit = req.query.limit ? Math.max(0, parseInt(req.query.limit, 10) || 0) : 20;
   try {
-    const props = await readCachedProps(sport);
+    const hasStore = !!(await cacheGet(`bookprices:${sport}`));
+    const props = await readGroupedProps(sport);
     const lines = bookComparison.bestLines(props, { side, limit });
-    return res.set(MISSION_HEADER).json({ sport, side, bestLines: lines, source: 'odds-cache' });
+    // `source` is the deploy fingerprint: 'bookprices' proves the new snapshot-
+    // locked store is serving; 'odds-cache' = falling back pre-first-snapshot.
+    return res.set(MISSION_HEADER).json({ sport, side, bestLines: lines, source: hasStore ? 'bookprices' : 'odds-cache' });
   } catch (err) {
     console.error(`[books/${sport}]`, err.message);
     return res.set(MISSION_HEADER).json({ sport, side, bestLines: [], source: 'odds-cache' });
@@ -59,10 +79,14 @@ router.get('/:sport/:player/:stat', async (req, res) => {
   const stat = req.params.stat;
   const side = req.query.side === 'under' ? 'under' : 'over';
   try {
-    const props = await readCachedProps(sport);
+    const props = await readGroupedProps(sport);
+    // Match on the normalized name key so "A.J. Ewing" / "AJ Ewing" resolve to
+    // the same player (the store is already normalized-keyed).
+    const wantKey = nameKey(player);
+    const wantStat = stat.toLowerCase();
     const prop = props.find(
-      (p) => (p.player || '').toLowerCase() === player.toLowerCase() &&
-        (p.stat_type || p.stat || '').toLowerCase() === stat.toLowerCase(),
+      (p) => nameKey(p.player || '') === wantKey &&
+        (p.stat_type || p.stat || '').toLowerCase() === wantStat,
     );
     if (!prop) {
       return res.status(404).set(MISSION_HEADER).json({ error: 'Prop not found in current slate.' });

src/services/bookComparisonService.js

@@ -30,22 +30,73 @@ function oddsForSide(line, side) {
   return raw == null ? null : Number(raw);
 }
 
+// Book Comparison order — the crown is PRE-REGISTERED and threshold-gated. It
+// stays OFF until Phase 2's spread measurement (scripts/measure-book-spread.js)
+// confirms the median same-line spread clears the bar (≥8¢ OR ≥2 implied-prob
+// pts). A crown over a flat market is a claim of edge that does not exist.
+function crownEnabled(opts) {
+  if (opts && opts.crownEnabled != null) return !!opts.crownEnabled;
+  return process.env.BOOK_CROWN_ENABLED === '1';
+}
+
+// Render every book row honestly, with NO crown. Used for single-book props,
+// props with no shared line, and whenever the crown flag is off.
+function honestGrid(prop, side, books) {
+  const rows = books.map((b) => ({
+    book: b.book,
+    line: b.line ?? null,
+    over_odds: b.over_odds ?? null,
+    under_odds: b.under_odds ?? null,
+    isBest: false,
+  }));
+  return {
+    player: prop.player,
+    stat: prop.stat_type || prop.stat,
+    line: prop.line ?? (books[0] && books[0].line) ?? null,
+    side,
+    books: rows,
+    bestBook: null,
+    bestOdds: null,
+    bookCount: new Set(books.map((b) => b.book)).size,
+    savings: 0,
+    crowned: false,
+  };
+}
+
 /**
  * Compare one grouped prop across its books for a given side.
- * Returns null when there are no usable book lines.
+ * Returns null when there are no usable book rows at all.
+ *
+ * HONEST-ABSENT: a single-book prop renders that one book — no crown, no implied
+ * second price, no savings claim. The crown fires ONLY among ≥2 books posting
+ * the SAME line with DIFFERING prices, and ONLY when the flag is enabled (Phase 2
+ * gate). Comparing prices across different lines is meaningless (Data Semantics).
  */
-function compareProp(prop, side = 'over') {
+function compareProp(prop, side = 'over', opts = {}) {
   const books = (prop?.lines || prop?.books || []).filter((b) => b && b.book);
-  const priced = books.filter((b) => Number.isFinite(oddsForSide(b, side)));
-  if (priced.length === 0) return null;
+  if (books.length === 0) return null;
 
-  let best = priced[0];
-  for (const b of priced) {
+  const priced = books.filter((b) => Number.isFinite(oddsForSide(b, side)));
+  // Single priced book, or crown disabled → honest grid, no crown.
+  if (priced.length < 2 || !crownEnabled(opts)) return honestGrid(prop, side, books);
+
+  // Crown only among books at the SAME line (the shared-line comparison set).
+  const byLine = {};
+  for (const b of priced) { const L = String(b.line); (byLine[L] = byLine[L] || []).push(b); }
+  let shared = [];
+  for (const rows of Object.values(byLine)) { if (rows.length > shared.length) shared = rows; }
+  const distinctBooks = new Set(shared.map((b) => b.book));
+  const distinctPrices = new Set(shared.map((b) => oddsForSide(b, side)));
+  // Fewer than 2 books at one line, or all books post the identical price →
+  // nothing to crown. Render honestly.
+  if (distinctBooks.size < 2 || distinctPrices.size < 2) return honestGrid(prop, side, books);
+
+  let best = shared[0];
+  for (const b of shared) {
     if (americanToDecimal(oddsForSide(b, side)) > americanToDecimal(oddsForSide(best, side))) best = b;
   }
-
   const bestDecimal = americanToDecimal(oddsForSide(best, side));
-  const avgDecimal = average(priced.map((b) => americanToDecimal(oddsForSide(b, side))));
+  const avgDecimal = average(shared.map((b) => americanToDecimal(oddsForSide(b, side))));
   const savings = Math.round((bestDecimal - avgDecimal) * 100 * 100) / 100; // per $100, 2dp
 
   return {
@@ -53,17 +104,19 @@ function compareProp(prop, side = 'over') {
     stat: prop.stat_type || prop.stat,
     line: best.line ?? prop.line ?? null,
     side,
-    books: priced.map((b) => ({
+    // Show all books; crown only the best AT THE SHARED LINE.
+    books: books.map((b) => ({
       book: b.book,
       line: b.line ?? null,
       over_odds: b.over_odds ?? null,
       under_odds: b.under_odds ?? null,
-      isBest: b.book === best.book,
+      isBest: b.book === best.book && Number(b.line) === Number(best.line),
     })),
     bestBook: best.book,
     bestOdds: oddsForSide(best, side),
-    bookCount: priced.length,
+    bookCount: distinctBooks.size,
     savings,
+    crowned: true,
   };
 }
 
@@ -72,12 +125,15 @@ function compareProp(prop, side = 'over') {
  * shopping matters most). Drops props with a single book (nothing to
  * compare). `limit` caps the result.
  */
-function bestLines(props, { side = 'over', limit = 20 } = {}) {
+function bestLines(props, { side = 'over', limit = 20, crownEnabled: ce } = {}) {
   if (!Array.isArray(props)) return [];
+  // "Best lines tonight" is inherently a crown claim — when the crown is gated
+  // off (Phase 2 not yet cleared) it makes no such claim.
+  if (!crownEnabled({ crownEnabled: ce })) return [];
   const out = [];
   for (const prop of props) {
-    const cmp = compareProp(prop, side);
-    if (cmp && cmp.bookCount >= 2) out.push(cmp);
+    const cmp = compareProp(prop, side, { crownEnabled: ce });
+    if (cmp && cmp.crowned && cmp.bookCount >= 2) out.push(cmp);
   }
   out.sort((a, b) => b.savings - a.savings);
   return limit > 0 ? out.slice(0, limit) : out;

src/services/bookPriceStore.js

@@ -0,0 +1,92 @@
+'use strict';
+
+/**
+ * bookPriceStore — DISPLAY-ONLY per-book price capture (Book Comparison order,
+ * Phase 1).
+ *
+ * WHY THIS EXISTS: `normalizeProps` emits one row per book, but every
+ * persistence point on the GRADE path collapses to a single book
+ * (gradeSlateService.dedupeProps keeps the first book per line;
+ * snapshotService.indexOdds keeps one row per player|stat; the grades cache,
+ * snapshot, and ledger each lock one price). The only place per-book prices
+ * survived was the transient odds cache (`odds:{sport}:{utcDate}`, ~1h TTL,
+ * raw player names, grade-path INPUT). This module captures them at snapshot
+ * time into a snapshot-locked, normalized-key, display-only store.
+ *
+ * STRUCTURAL FENCE (not a comment — an enforced property):
+ *   1. This module ONLY reads a props array and RETURNS a new object. It never
+ *      mutates the props it is handed (a bookPriceStore.test.js case deep-freezes
+ *      the input and asserts capture succeeds).
+ *   2. Its output is written to its OWN Redis key (`bookprices:{sport}`), read by
+ *      NOTHING on the grade path — not gradeSlateService, snapshotService's dedup,
+ *      indexOdds, any challenger, the ledger, edge_pct/ev_pct, or the selector.
+ *      A test greps the grade-path files and asserts zero `bookprices` references.
+ *   3. In runSnapshot the capture is a leaf `cacheSet` whose result is assigned to
+ *      no variable used downstream — the grade-byte-identical test proves the
+ *      graded slate is unchanged whether or not the capture runs.
+ *
+ * So no value this file produces can ever reach a grade, a locked line, a
+ * challenger, the ledger, or the hero. It is a pure display leaf.
+ */
+
+const { nameKey, normalizeName } = require('../utils/playerName');
+
+/** Canonical lookup key for a graded prop's book rows. */
+function bookKey(player, statType) {
+  return `${nameKey(player)}|${String(statType || '').toLowerCase()}`;
+}
+
+/**
+ * Group a flat multi-book props array (oddsNormalizer shape) into one entry per
+ * normalized player+stat, each carrying every real book row. Rows with no price
+ * on EITHER side are dropped (nothing to compare — honest-absent, never a
+ * fabricated price). Never mutates `props`.
+ *
+ * @returns {{ updated_at, props: Array, count }}
+ */
+function captureBookPrices(props, opts = {}) {
+  const now = opts.now || (() => new Date().toISOString());
+  const ts = now();
+  const byKey = new Map();
+
+  for (const p of props || []) {
+    if (!p || !p.player || !p.stat_type || p.line == null || !p.book) continue;
+    // A row with neither price is not a comparable book row.
+    if (p.over_odds == null && p.under_odds == null) continue;
+
+    const stat = String(p.stat_type).toLowerCase();
+    const key = bookKey(p.player, stat);
+    if (!byKey.has(key)) {
+      byKey.set(key, {
+        key,
+        player: normalizeName(p.player).display || p.player,
+        stat_type: stat,
+        books: [],
+      });
+    }
+    const entry = byKey.get(key);
+    // A book appears once per line. Keep the FIRST row for a given book+line
+    // (mirrors dedupeProps' first-wins, applied here only for display de-dup —
+    // it does NOT feed grading).
+    const bl = `${p.book}|${p.line}`;
+    if (entry.books.some((b) => `${b.book}|${b.line}` === bl)) continue;
+    entry.books.push({
+      book: p.book,
+      line: Number(p.line),
+      over_odds: p.over_odds ?? null,
+      under_odds: p.under_odds ?? null,
+    });
+  }
+
+  const out = [...byKey.values()];
+  return { updated_at: ts, props: out, count: out.length };
+}
+
+/** Books posting a given line for a prop entry (shared-line comparison set). */
+function booksAtLine(entry, line) {
+  if (!entry || !Array.isArray(entry.books) || line == null) return [];
+  const L = Number(line);
+  return entry.books.filter((b) => Number(b.line) === L);
+}
+
+module.exports = { captureBookPrices, bookKey, booksAtLine };

src/services/snapshotService.js

@@ -284,6 +284,10 @@ async function runSnapshot(sport, opts = {}) {
     // suite that doesn't know about this dep can never make a live ESPN call.
     // Session 64 — model-snapshot retention. Injectable; null disables it.
     retention: opts.retention !== undefined ? opts.retention : require('./retentionService'),
+    // Book Comparison order (Phase 1) — DISPLAY-ONLY per-book price capture.
+    // Fenced: written to its own `bookprices:{sport}` key, read by nothing on
+    // the grade path. Injectable; a failure never touches grading.
+    captureBookPrices: opts.captureBookPrices || require('./bookPriceStore').captureBookPrices,
     refreshTeamStats: opts.refreshTeamStats
       || (process.env.NODE_ENV === 'test'
         ? async () => null
@@ -335,6 +339,21 @@ async function runSnapshot(sport, opts = {}) {
     console.warn(`[snapshot] game binding failed for ${sp} (rows without a real game time will be skipped):`, e.message);
   }
 
+  // Book Comparison order (Phase 1) — CAPTURE PER-BOOK PRICES BEFORE DEDUP.
+  // `props` still carries one row per book here (dedupeProps runs downstream
+  // inside gradeAndCacheSlate). The capture only READS props and writes its own
+  // `bookprices:{sport}` key at SNAP_TTL — long enough to outlive the cron gap
+  // (the 1h odds cache would blank between runs). Best-effort and structurally
+  // fenced: nothing on the grade path reads this key, and the graded slate is
+  // byte-identical whether or not this runs (bookPriceStore.test.js locks it).
+  try {
+    const bookStore = deps.captureBookPrices(props, { now: deps.now });
+    await deps.cacheSet(`bookprices:${sp}`, bookStore, SNAP_TTL);
+    console.log(`[snapshot] book prices ${sp}: ${bookStore.count} props with book rows captured`);
+  } catch (e) {
+    console.warn(`[snapshot] book-price capture failed for ${sp} (display-only, grading continues):`, e.message);
+  }
+
   // Session 63 — REFRESH TEAM STATS BEFORE GRADING.
   // `refreshTeamStats` is the ONLY writer of `team_stats:{sport}:{abbr}`, which
   // is the ONLY source of `opp_rank_stat` — and it had zero production callers,

tests/integration/session28Routes.test.js

@@ -75,22 +75,55 @@ describe('GET /api/lines/:sport/movers', () => {
 describe('GET /api/books/:sport', () => {
   const app = () => mount('/api/books', '../../src/routes/bookComparison');
 
-  test('returns best lines from cached props', async () => {
-    mockStore[`odds:nba:${new Date().toISOString().split('T')[0]}`] = {
+  // Book Comparison order: /api/books/:sport is a crown claim ("best lines
+  // tonight"), so it is gated OFF until Phase 2's spread measurement clears the
+  // bar — even with data it returns []. `source` is the deploy fingerprint.
+  test('reads the snapshot-locked bookprices store; makes no crown claim while gated off', async () => {
+    mockStore['bookprices:nba'] = {
       props: [
-        {
-          player: 'Wemby', stat_type: 'points',
-          lines: [
-            { book: 'dk', over_odds: -110 },
-            { book: 'fd', over_odds: -105 },
-          ],
-        },
+        { player: 'Wemby', stat_type: 'points', books: [
+          { book: 'draftkings', line: 28.5, over_odds: -110 },
+          { book: 'fanduel', line: 28.5, over_odds: -105 },
+        ] },
       ],
     };
     const res = await request(app()).get('/api/books/nba');
     expect(res.status).toBe(200);
+    expect(res.body.source).toBe('bookprices'); // new store is serving
+    expect(res.body.bestLines).toEqual([]);      // crown gated off → no claim
+  });
+
+  test('crown ENABLED → crowns the best price from the store', async () => {
+    process.env.BOOK_CROWN_ENABLED = '1';
+    mockStore['bookprices:nba'] = {
+      props: [
+        { player: 'Wemby', stat_type: 'points', books: [
+          { book: 'draftkings', line: 28.5, over_odds: -110 },
+          { book: 'fanduel', line: 28.5, over_odds: -105 },
+        ] },
+      ],
+    };
+    const res = await request(app()).get('/api/books/nba');
+    delete process.env.BOOK_CROWN_ENABLED;
+    expect(res.status).toBe(200);
     expect(res.body.bestLines).toHaveLength(1);
-    expect(res.body.bestLines[0].bestBook).toBe('fd');
+    expect(res.body.bestLines[0].bestBook).toBe('fanduel');
+  });
+
+  test('per-prop endpoint returns the honest grid (all books, no crown) even gated off', async () => {
+    mockStore['bookprices:nba'] = {
+      props: [
+        { player: 'Wemby', stat_type: 'points', books: [
+          { book: 'draftkings', line: 28.5, over_odds: -110 },
+          { book: 'fanduel', line: 28.5, over_odds: -105 },
+        ] },
+      ],
+    };
+    const res = await request(app()).get('/api/books/nba/Wemby/points');
+    expect(res.status).toBe(200);
+    expect(res.body.books).toHaveLength(2);
+    expect(res.body.books.every((b) => b.isBest === false)).toBe(true);
+    expect(res.body.bestBook).toBeNull();
   });
 
   test('empty when no cached props', async () => {

tests/unit/bookComparisonService.test.js

@@ -1,4 +1,10 @@
-// Unit: book comparison service (Session 28). Pure functions.
+// Unit: book comparison service. Pure functions.
+// Book Comparison order (Phase 3) — the crown is now HONEST + threshold-gated:
+//   - single-book / flat-market props render with NO crown
+//   - the crown fires only among ≥2 books at the SAME line with DIFFERING prices
+//   - and only when enabled (BOOK_CROWN_ENABLED / opts.crownEnabled), OFF until
+//     Phase 2's spread measurement clears the bar.
+// The crown-logic cases below pass { crownEnabled: true } explicitly.
 
 const { compareProp, bestLines } = require('../../src/services/bookComparisonService');
 
@@ -12,9 +18,11 @@ const prop = {
   ],
 };
 
-describe('bookComparisonService — compareProp', () => {
+describe('compareProp — crown enabled (real spread)', () => {
+  const on = { crownEnabled: true };
   test('identifies the best OVER line (highest payout)', () => {
-    const c = compareProp(prop, 'over');
+    const c = compareProp(prop, 'over', on);
+    expect(c.crowned).toBe(true);
     expect(c.bestBook).toBe('fanduel'); // -105 pays more than -110/-120
     expect(c.bestOdds).toBe(-105);
     expect(c.books.find((b) => b.book === 'fanduel').isBest).toBe(true);
@@ -22,42 +30,73 @@ describe('bookComparisonService — compareProp', () => {
   });
 
   test('identifies the best UNDER line', () => {
-    const c = compareProp(prop, 'under');
+    const c = compareProp(prop, 'under', on);
     expect(c.bestBook).toBe('betmgm'); // -102 pays more than -110/-115
     expect(c.bestOdds).toBe(-102);
   });
 
   test('savings is positive (best beats the field average)', () => {
-    const c = compareProp(prop, 'over');
-    expect(c.savings).toBeGreaterThan(0);
+    expect(compareProp(prop, 'over', on).savings).toBeGreaterThan(0);
+  });
+});
+
+describe('compareProp — honest-absent', () => {
+  test('single-book prop renders the one book, NO crown', () => {
+    const c = compareProp({ player: 'X', stat_type: 'hits', lines: [{ book: 'dk', line: 0.5, over_odds: -110 }] }, 'over', { crownEnabled: true });
+    expect(c.bookCount).toBe(1);
+    expect(c.bestBook).toBeNull();
+    expect(c.crowned).toBe(false);
+    expect(c.books[0].isBest).toBe(false);
+    expect(c.savings).toBe(0);
   });
 
-  test('single-book prop still compares (bookCount 1)', () => {
-    const c = compareProp({ player: 'X', stat_type: 'hits', lines: [{ book: 'dk', over_odds: -110 }] }, 'over');
-    expect(c.bookCount).toBe(1);
-    expect(c.bestBook).toBe('dk');
+  test('crown DISABLED by default → multi-book prop shows all books, none crowned', () => {
+    const c = compareProp(prop, 'over'); // no opts → env default (off in tests)
+    expect(c.crowned).toBe(false);
+    expect(c.books.every((b) => b.isBest === false)).toBe(true);
+    expect(c.bestBook).toBeNull();
+  });
+
+  test('identical prices at the same line → no crown even when enabled', () => {
+    const flat = { player: 'X', stat_type: 'hits', lines: [
+      { book: 'draftkings', line: 0.5, over_odds: -110, under_odds: -110 },
+      { book: 'fanduel', line: 0.5, over_odds: -110, under_odds: -110 },
+    ] };
+    expect(compareProp(flat, 'over', { crownEnabled: true }).crowned).toBe(false);
   });
 
   test('no usable lines → null, not crash', () => {
     expect(compareProp({ player: 'X', stat_type: 'hits', lines: [] }, 'over')).toBeNull();
     expect(compareProp({ player: 'X', stat_type: 'hits' }, 'over')).toBeNull();
   });
+
+  test('reads a grouped `books` array (bookprices store shape)', () => {
+    const c = compareProp({ player: 'Y', stat_type: 'hits', books: [
+      { book: 'draftkings', line: 1.5, over_odds: -115 },
+      { book: 'betmgm', line: 1.5, over_odds: -105 },
+    ] }, 'over', { crownEnabled: true });
+    expect(c.bestBook).toBe('betmgm');
+  });
 });
 
-describe('bookComparisonService — bestLines', () => {
-  test('drops single-book props and sorts by savings desc', () => {
+describe('bestLines', () => {
+  test('makes no crown claim when gated off (returns [])', () => {
+    expect(bestLines([prop], { side: 'over', crownEnabled: false })).toEqual([]);
+  });
+
+  test('enabled: drops single-book props and sorts by savings desc', () => {
     const props = [
       prop,
-      { player: 'Solo', stat_type: 'reb', lines: [{ book: 'dk', over_odds: -110 }] }, // 1 book → dropped
+      { player: 'Solo', stat_type: 'reb', lines: [{ book: 'dk', line: 5.5, over_odds: -110 }] }, // 1 book → dropped
       {
         player: 'BigEdge', stat_type: 'ast',
         lines: [
-          { book: 'dk', over_odds: -200 },
-          { book: 'fd', over_odds: +120 }, // huge spread → big savings
+          { book: 'dk', line: 5.5, over_odds: -200 },
+          { book: 'fd', line: 5.5, over_odds: +120 }, // huge spread → big savings
         ],
       },
     ];
-    const lines = bestLines(props, { side: 'over' });
+    const lines = bestLines(props, { side: 'over', crownEnabled: true });
     expect(lines.map((l) => l.player)).not.toContain('Solo');
     expect(lines[0].player).toBe('BigEdge'); // biggest savings first
   });

tests/unit/bookPriceStore.test.js

@@ -0,0 +1,135 @@
+// Book Comparison order (Phase 1) — display-only per-book price store.
+// Locks: capture correctness, the STRUCTURAL FENCE (no mutation, no grade-path
+// read), and grade-byte-identical proof through runSnapshot.
+
+const fs = require('fs');
+const path = require('path');
+const { captureBookPrices, bookKey, booksAtLine } = require('../../src/services/bookPriceStore');
+const snapshot = require('../../src/services/snapshotService');
+
+// One prop (Judge TB 1.5) across 3 books at the shared line + a 1-book prop.
+const multiBookProps = [
+  { player: 'Aaron Judge', stat_type: 'total_bases', line: 1.5, over_odds: -115, under_odds: -105, book: 'draftkings' },
+  { player: 'Aaron Judge', stat_type: 'total_bases', line: 1.5, over_odds: -110, under_odds: -110, book: 'betmgm' },
+  { player: 'Aaron Judge', stat_type: 'total_bases', line: 1.5, over_odds: -120, under_odds: 100, book: 'pinnacle' },
+  { player: 'Mookie Betts', stat_type: 'hits', line: 1.5, over_odds: 120, under_odds: -150, book: 'draftkings' },
+];
+
+describe('captureBookPrices — capture correctness', () => {
+  it('groups one entry per normalized player+stat with every real book row', () => {
+    const out = captureBookPrices(multiBookProps, { now: () => 'T' });
+    expect(out.updated_at).toBe('T');
+    expect(out.count).toBe(2);
+    const judge = out.props.find((p) => p.key === bookKey('Aaron Judge', 'total_bases'));
+    expect(judge.player).toBe('Aaron Judge');
+    expect(judge.books).toHaveLength(3);
+    expect(judge.books.map((b) => b.book).sort()).toEqual(['betmgm', 'draftkings', 'pinnacle']);
+    const betts = out.props.find((p) => p.key === bookKey('Mookie Betts', 'hits'));
+    expect(betts.books).toHaveLength(1); // single-book prop kept honestly
+  });
+
+  it('drops rows with no price on either side (never a fabricated row)', () => {
+    const out = captureBookPrices([
+      { player: 'X', stat_type: 'hits', line: 0.5, over_odds: null, under_odds: null, book: 'draftkings' },
+    ]);
+    expect(out.count).toBe(0);
+  });
+
+  it('de-dupes a repeated book+line (first row wins) and requires book/line', () => {
+    const out = captureBookPrices([
+      { player: 'X', stat_type: 'hits', line: 0.5, over_odds: -110, under_odds: -110, book: 'draftkings' },
+      { player: 'X', stat_type: 'hits', line: 0.5, over_odds: 999, under_odds: 999, book: 'draftkings' },
+      { player: 'X', stat_type: 'hits', line: 0.5, over_odds: -110, book: null }, // no book → skip
+    ]);
+    expect(out.props[0].books).toHaveLength(1);
+    expect(out.props[0].books[0].over_odds).toBe(-110); // first-wins
+  });
+
+  it('booksAtLine restricts to the shared line only', () => {
+    const entry = { books: [{ book: 'a', line: 1.5 }, { book: 'b', line: 1.5 }, { book: 'c', line: 2.5 }] };
+    expect(booksAtLine(entry, 1.5).map((b) => b.book)).toEqual(['a', 'b']);
+    expect(booksAtLine(entry, 2.5)).toHaveLength(1);
+  });
+});
+
+describe('STRUCTURAL FENCE', () => {
+  it('never mutates the props it reads (deep-frozen input)', () => {
+    const frozen = multiBookProps.map((p) => Object.freeze({ ...p }));
+    Object.freeze(frozen);
+    expect(() => captureBookPrices(frozen)).not.toThrow();
+  });
+
+  it('no grade-path module references the bookprices store', () => {
+    const gradePathFiles = [
+      'src/services/gradeSlateService.js',
+      'src/services/ledgerService.js',
+      'src/services/challengerProjection.js',
+      'src/services/contactChallenger.js',
+      'src/services/projectionChallenger.js',
+      'src/services/intelligence/analyzeViaEngine1.js',
+    ];
+    for (const rel of gradePathFiles) {
+      const src = fs.readFileSync(path.join(__dirname, '../../', rel), 'utf8');
+      expect(src).not.toMatch(/bookprices/);
+      expect(src).not.toMatch(/bookPriceStore/);
+    }
+  });
+});
+
+describe('GRADE BYTE-IDENTICAL through runSnapshot', () => {
+  function memCache() {
+    const store = {};
+    return {
+      store,
+      cacheGet: async (k) => (k in store ? store[k] : null),
+      cacheSet: async (k, v) => { store[k] = v; },
+    };
+  }
+  const grades = [
+    { player: 'Aaron Judge', stat_type: 'total_bases', line: 1.5, direction: 'over', grade: 'A', confidence: 71, edge_pct: 4.2 },
+    { player: 'Mookie Betts', stat_type: 'hits', line: 1.5, direction: 'under', grade: 'B', confidence: 60, edge_pct: 1.1 },
+  ];
+  const fakeGrade = () => async (_s, _p, opts) => {
+    await opts.cacheSet('grades:x', { grades, updated_at: opts.now(), source: 'test' });
+    return { written: true, count: grades.length };
+  };
+  const baseOpts = (cache, extra = {}) => ({
+    getOdds: async () => ({ props: multiBookProps, provider: 'test' }),
+    gradeAndCacheSlate: fakeGrade(),
+    resolveStats: async () => ({ found: false }),
+    classify: () => ({ primary: null }),
+    cacheGet: cache.cacheGet,
+    cacheSet: cache.cacheSet,
+    now: () => '2026-07-27T00:00:00.000Z',
+    nowMs: () => 1000,
+    notify: async () => {},
+    retention: null,
+    ledger: { recordPipelineGrades: async () => ({ written: 0 }), captureClosing: async () => {}, __internals: require('../../src/services/ledgerService').__internals },
+    refreshTeamStats: async () => null,
+    buildEspnIndex: async () => ({}),
+    gameBinder: { attachGameTimes: async () => ({ bound: 0, alreadyHad: 2, unresolved: 0, ambiguous: 0 }) },
+    ...extra,
+  });
+
+  it('produces identical grades whether or not the capture runs, and writes the fenced key', async () => {
+    // WITH capture (default dep).
+    const c1 = memCache();
+    await snapshot.runSnapshot('mlb', baseOpts(c1));
+    // WITHOUT capture (inject a no-op that writes nothing).
+    const c2 = memCache();
+    await snapshot.runSnapshot('mlb', baseOpts(c2, { captureBookPrices: () => ({ updated_at: 'x', props: [], count: 0 }) }));
+
+    const strip = (snap) => JSON.stringify((snap.grades || []).map((g) => ({
+      player: g.player, stat_type: g.stat_type, line: g.line, direction: g.direction,
+      grade: g.grade, gradedAt: g.gradedAt,
+    })));
+    expect(strip(c1.store['snapshot:mlb:latest'])).toBe(strip(c2.store['snapshot:mlb:latest']));
+    expect(JSON.stringify(c1.store['grades:mlb'].grades.map((g) => g.grade)))
+      .toBe(JSON.stringify(c2.store['grades:mlb'].grades.map((g) => g.grade)));
+
+    // The fenced store IS written, with real book rows.
+    const bp = c1.store['bookprices:mlb'];
+    expect(bp.count).toBe(2);
+    expect(bp.props.find((p) => p.stat_type === 'total_bases').books).toHaveLength(3);
+  });
+});