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
}

E-Invoice Validation Pipeline