E-Invoice Validation Pipeline

Note (dated 2026-08-04): a chain composes independent computations performed in an analytical order. No step's output is carried into the next step by the execution model; each step computes from its own declared inputs. This is true of every chain on this site, including chains whose per-step copy below reads as a data handoff.

Gated four-step e-invoice validation pipeline. Checks a supplied e-invoice extract against version-pinned Factur-X, XRechnung, PINT-AE, MyInvois, Peppol BIS 3.0 (Belgium, mandatory since 2026-01-01), or KSeF FA(3) (Poland, mandatory-use phase-in from 2026-02-01) format rules, recomputes VAT arithmetic against the document-asserted amounts, routes the transaction to its applicable jurisdiction mandate, and composes a hash-anchored transmission receipt carrying the SPEC.md §27 pre-transmission release gate (review_required, schema-only pending HA-RETRO-1). Exits immediately on a format-conformance failure or a VAT-arithmetic mismatch, so the receipt is only ever built for a document that passed both gates.

OpenChainGraph · 4 Steps compliance mandate · §21.4 Gates Hash-Anchored §4 chain_depth:4 Client-Side · Zero PII

Chain Stages · 4 Steps · 2 Decision Gates (§21.4)

1 ROOT / GATE node §21.4 gate

E-Invoice Format Validator art-293-einvoice-format-validator

structural_completeness feeds Stage 2 VAT verification; a format failure stops the chain

△ Gate: if /structural_completeness == false → END | else → Step 2

MCP Call · validate_einvoice_format

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "validate_einvoice_format",
    "arguments": {
      "document": {
        "format": "xrechnung",
        "fields": {"invoice_number": "INV-1", "invoice_date": "2026-09-15", "currency_code": "EUR", "seller_name": "Acme GmbH", "seller_vat_id": "DE123456789", "buyer_name": "Buyer SAS", "leitweg_id": "04011000-12345-67"},
        "line_items": [{"line_id": 1, "net_amount": 1000, "vat_category": "S", "vat_rate_pct": 19}]
      }
    }
  },
  "id": 1
}

↓

2 GATE node §21.4 gate

E-Invoice VAT Calculation Verifier art-294-einvoice-vat-calc-verifier

consistent feeds Stage 3 mandate routing; a VAT-arithmetic mismatch stops the chain

△ Gate: if /consistent == false → END | else → Step 3

MCP Call · verify_einvoice_vat_calc

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "verify_einvoice_vat_calc",
    "arguments": {
      "document": {
        "line_items": [{"line_id": 1, "net_amount": 1000, "vat_category": "S", "vat_rate_pct": 19}],
        "tax_subtotals_asserted": [{"vat_category": "S", "vat_rate_pct": 19, "taxable_amount": 1000, "tax_amount": 190}],
        "grand_total_asserted": 1190,
        "tax_total_asserted": 190
      },
      "rounding": {"method": "half-up", "granularity": "per-line"}
    }
  },
  "id": 2
}

↓

3 STEP node

E-Invoice Jurisdiction Mandate Router art-295-einvoice-jurisdiction-mandate-router

routed_mandate feeds the terminal transmission receipt

MCP Call · route_einvoice_jurisdiction_mandate

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "route_einvoice_jurisdiction_mandate",
    "arguments": {
      "supplier_country": "DE",
      "buyer_country": "FR",
      "transaction_type": "B2B",
      "transaction_date": "2026-09-15"
    }
  },
  "id": 3
}

↓

4 TERMINAL node

E-Invoice Transmission Receipt Builder art-296-einvoice-transmission-receipt-builder

Composes the hash-anchored transmission receipt — final stage (only reached if gates 1 and 2 pass)

MCP Call · build_einvoice_transmission_receipt

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "build_einvoice_transmission_receipt",
    "arguments": {
      "document": {"document_sha256": "", "format": "xrechnung"},
      "format_validation": {"structural_completeness": true},
      "vat_verification": {"consistent": true},
      "routed_mandate": {"regime_country": "FR", "applicable_format": "factur-x_or_ubl", "mandatory_from": "2026-09-01", "phase_status": "mandatory", "transmission_channel": "PDP"}
    }
  },
  "id": 4
}

Question: We just won a customer in Germany while our e-invoicing was built for France. What format and channel does the mandate table demand there? Run the AINumbers MCP tool `run_chain` with {"chain":"einvoice-validation-pipeline"} and read `art-295-einvoice-jurisdiction-mandate-router.applicable_format`. Re-run with `inputs` for `art-295-einvoice-jurisdiction-mandate-router`, reusing the values that result echoed, with `buyer_country` set to "DE". Compare the same field. Verify: call `verify_execution_hash` (https://mcp.ainumbers.co/mcp) with `claimed_hash` set to `composite_execution_hash` and the full `composite_artifact`. Ledger, for a human re-check: https://ledger.ainumbers.co/ PII rule: send synthetic or anonymised inputs only. The MCP server runs these kernels and logs no payloads. Chain page: https://ainumbers.co/chaingraph/chains/einvoice-validation-pipeline.html

E-Invoice Validation Pipeline

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