# 7B - snapshot_inventory_and_coverage

## Snapshot Inventory (Observed)

### Runtime-wired snapshot source (`docs/ARCH/2020экспорт`)

| File | Bytes | Records | Runtime wired |
|---|---:|---:|---|
| `03_snapshot_fragment_problem_cases.json` | 302,520 | 80 | yes |
| `04_samples_SpisanieSRaschetnogoScheta.json` | 196,178 | 27 | yes |
| `05_samples_RealizaciyaTovarovUslug.json` | 132,032 | 5 | yes |
| `06_samples_PostuplenieTovarovUslug.json` | 181,409 | 10 | yes |
| `07_samples_DocumentJournals.json` | 292,931 | 80 | yes |
| `08_samples_NDS_registers.json` | 291,547 | 80 | yes |
| `09_samples_key_fields_Recorder_Ref_Supplier_Buyer_Responsible.json` | 511,133 | 140 | yes |
| **Total** | **1,907,750** | **422** |  |

Code proof:
- `backend/src/config.ts`: `ARCH_EXPORT_2020_DIR`.
- `backend/src/services/assistantDataLayer.ts`: `ensureData()` reads files 03/04/05/06/07/08/09.

### Monthly as-of corpus (`docs/ARCH/2020_monthly_company_asof_full/_tmp_ndjson`)

| Asset | Value |
|---|---|
| NDJSON files | 12 (`snapshot_2020-01` ... `snapshot_2020-12`) |
| Total size | 7,059,009,054 bytes (~7.06 GB) |
| Runtime wired in backend path | no direct reference found |

## Coverage Reality

| Question class | Snapshot-only coverage | Reality |
|---|---|---|
| Settlement chain diagnostics | partial | Works for sample-level hints, but temporal/polarity drift still appears in traces |
| VAT document-register-book chain | partial to good | Better in VAT-specific cases, but cross-domain contamination still occurs in mixed traces |
| Month-close / RBP diagnostics | partial to good | Core traces exist, but still often `partial_coverage` with weak-confidence qualifiers |
| Strict as-of monthly proof | not covered | Large monthly corpus exists, but runtime retrieval path is not wired to it |

## Audit Artifacts

- `audit_artifacts/snapshot_inspection/snapshot_2020_export_inventory.json`
- `audit_artifacts/snapshot_inspection/monthly_asof_ndjson_inventory.json`
- `audit_artifacts/snapshot_inspection/runtime_snapshot_wiring.md`