skills/go-clearing-settlement-reconciliation/references/reconciliation-model.md

# Reconciliation model

1. Acquire and authenticate source evidence.
2. Store immutable artifact identity, checksum, completeness evidence, and supersession lineage.
3. Parse with a versioned deterministic parser.
4. Normalize identities, amounts, currencies, and lifecycle.
5. Build explicit 1:1, 1:N, or N:1 groups whose currency-preserving equation balances.
6. Classify unmatched and mismatched items.
7. Age timing differences.
8. Authorize and post linked adjustments.
9. Re-run safely, preserve decisions, and turn corrected artifacts into explicit rematch or reversal work.
10. Prove source and processing completeness.

Every normalized component belongs to one match group or one exception. Matching the same item into two groups is a financial-integrity defect even when aggregate totals agree.