Files
vyndr/scripts/verify-artifact-reconstruction.js
builtbykev 3184c05d51 fit_as_of does not pin a training set; training_cutoff does
The reconstruction verifier re-walked the ledger bounded by `fit_as_of` and
reported DIFFERS for a completely healthy artifact. The artifact had not moved —
its knot, curve and source digests on disk were byte-identical and the runtime
was serving exactly them. The TRAINING SOURCE had moved.

Measured: the artifact was built at 05:xx UTC with 6,069 rows through
2026-09-01. By 20:00 UTC a re-walk at the same fit_as_of returned 6,237, because
2026-09-02's 168 rows settled in between. Settlement backfills dates that are
already before the cutoff, so `fit_as_of` bounds eligibility but does not pin
membership.

`training_cutoff` — the newest observation actually admitted — does pin it,
because those dates are fully settled. Re-walked under that bound the
reconstruction is EXACT: fit_n, training_cutoff, source_digest, knot_count,
knot_digest, served_curve_digest all equal and the curve identical.

This is why the two fields were kept separate and why source_digest exists. The
digest caught a moving source and refused to call it a match, which is the
behaviour that made the diagnosis possible.

No artifact change. No model change. The verifier now states the bound it used.

Suite 405/405.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CQJeAG8vcDoL5zkiaJyVb8
2026-09-03 16:12:27 -04:00

85 lines
3.8 KiB
JavaScript

#!/usr/bin/env node
'use strict';
/**
* verify-artifact-reconstruction — rebuild the promoted artifact from its
* DECLARED TRAINING CONTRACT and require exact equality.
*
* A fresh read, a fresh source digest, a fresh fit, fresh digests. Calling the
* same builder twice would prove only that the builder is deterministic; this
* proves the artifact is derivable from what it says about itself.
*/
require('dotenv').config({ quiet: true });
const crypto = require('crypto');
const { createClient } = require('@supabase/supabase-js');
const cal = require('../src/services/model/calibration');
const src = require('../src/services/model/currentEraSource');
const registry = require('../src/services/model/artifactRegistry');
const digest = (o) => crypto.createHash('sha256').update(JSON.stringify(o)).digest('hex').slice(0, 16);
function servedCurve(map, bands) {
const steps = []; let prev = null;
for (const [lo, hi] of bands) {
prev = null;
for (let x = lo; x < hi - 1e-9; x += 0.001) {
const raw = Math.round(x * 1000) / 1000;
const v = cal.applyIsotonic(map, raw);
if (v === null) continue;
const r = Math.round(v * 1e6) / 1e6;
if (r !== prev) { steps.push([raw, r]); prev = r; }
}
}
return steps;
}
(async () => {
const sb = createClient(process.env.SUPABASE_URL, process.env.SUPABASE_SERVICE_KEY,
{ auth: { persistSession: false } });
const a = registry.load('mlb', 'hits');
if (!a) throw new Error('no promoted artifact');
// BOUND BY `training_cutoff`, NOT `fit_as_of`.
//
// `fit_as_of` is the eligibility bound the ORIGINAL walk used, but it does not
// pin the training set: settlement backfills. Measured 2026-09-03 — the
// artifact was built at 05:xx UTC with 6,069 rows through 2026-09-01, and by
// 20:00 UTC a re-walk at the same `fit_as_of` returned 6,237, because
// 2026-09-02's 168 rows had settled in between. Reconstruction against
// `fit_as_of` therefore reports DIFFERS for a completely healthy artifact.
//
// `training_cutoff` is the newest observation actually admitted, and those
// dates are fully settled, so it is stable. `lt` is exclusive, so the bound is
// the day AFTER the cutoff.
const cutoffDay = new Date(`${a.training_cutoff}T00:00:00Z`);
cutoffDay.setUTCDate(cutoffDay.getUTCDate() + 1);
const bound = cutoffDay.toISOString().slice(0, 10);
const rows = await src.loadRows(sb, {
sport: a.sport, stat: a.stat, modelVersion: a.model_version, before: bound,
});
rows.sort((x, y) => (x.date < y.date ? -1 : x.date > y.date ? 1 : (x.id < y.id ? -1 : 1)));
const audit = src.eraAudit(rows, a.model_version);
const map = cal.fitIsotonic(rows, { minTotal: 200 });
const curve = servedCurve(map, a.certified_bands);
const got = {
fit_n: rows.length,
training_cutoff: rows.length ? rows[rows.length - 1].date : null,
source_digest: src.sourceDigest(rows),
knot_count: map ? map.length : null,
knot_digest: digest(map),
served_curve_digest: digest(curve),
wrong_era_rows: audit.wrong_era_rows,
};
const want = {
fit_n: a.fit_n, training_cutoff: a.training_cutoff, source_digest: a.source_digest,
knot_count: a.knot_count, knot_digest: a.knot_digest,
served_curve_digest: a.served_curve_digest, wrong_era_rows: 0,
};
const mismatches = Object.keys(want).filter((k) => got[k] !== want[k]);
console.log(JSON.stringify({ artifact_id: a.artifact_id, bound_used: `game_date < ${bound}`, want, got,
curve_identical: JSON.stringify(curve) === JSON.stringify(a.served_curve),
mismatches, RECONSTRUCTION: mismatches.length === 0 && JSON.stringify(curve) === JSON.stringify(a.served_curve)
? 'EXACT' : 'DIFFERS' }, null, 1));
process.exit(mismatches.length === 0 ? 0 : 1);
})().catch((e) => { console.error(e.message); process.exit(1); });