Files
vyndr/specs/audit-data
builtbykev 3fe840ab83 Diagnose grade collapse + find the DEAD probability layer (report only)
Kev's call: investigate the B/C grade collapse before building. Report
only — no grade logic, thresholds, or engine code touched.

FINDING 1 — the collapse is real, live and structural. Across 604 ledger
rows and both sports the engine has emitted exactly TWO grades (B, C) and
NINE confidence values (63/57/55/52/47/45/35/25/20), ceiling 63. Still
true today on both sports. Confidence does NOT determine the letter:
conf 45 -> B while 47 and 52 -> C (non-monotonic), so the surfaced
confidence is not the quantity the letter came from. Edge scale still
broken: 311/604 rows exceed the frontend's sane cap of 40, 39 exceed 100,
worst 620.

FINDING 2 (bigger) — the entire probability layer is DEAD in production.
Live /api/snapshot/mlb: p_win, kelly, ev_pct, model_odds and value are
absent on 0/8 grades, while alt_lines (Desk-gated) IS present 8/8 —
proving nothing is tier-stripped, they are simply never computed.

Root cause: gameLogService.pythonPath returns null for MLB by
construction and the Python service is offline for NBA/WNBA, so
meta.gameLogs is [] for every sport; estimateProbability returns
p_over null; every field guarded by `if (pWin != null)` is skipped.
This is the S46 bug in a second location — that fix added an MLB branch
to featureCache.gameLogFeatures (which is why grades/projections still
work) but never to the estimator path.

Consequences: EV — the Model Train's whole ranking signal — has never
been computed on a live prop. Hero v2 matches nothing and always falls
through to the recent-read fallback (live /api/hero-prop returns
is_recent:true). Quarter-Kelly, sold on the pricing page and listed BUILT
in PROMISE-AUDIT.md, never runs. The value triplet is a duet live.

Recommend re-sequencing: revive the probability layer BEFORE G-a and
C-led (C-led would persist a column of nulls; G-a's EV_FLEX_THRESHOLD
would gate on a permanently-null value — Kev's EV_FLEX_ENFORCE=0 ruling
accidentally prevented an outage). featureCache:206-226 already has both
adapter branches and is the template.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SmNjJAwEnqHPtXbvSZR8kA
2026-07-19 18:13:06 -04:00
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