About InvoiceIn
InvoiceIn is a hosted service that converts received e-invoices into canonical EN 16931 JSON and validation reports with plain-language repair hints. It supports European and UAE formats and can also produce PDF, CSV, and DATEV exports.
Key features
- 01Parse multiple e-invoice formats
- 02Canonical EN 16931 JSON output
- 03Validation reports with fix hints
- 04PDF, CSV, and DATEV exports
- 05In-memory processing without storage
Use cases
- 01Normalize invoices from multiple markets
- 02Review validation errors and suggested fixes
- 03Export invoice data for accounting workflows
MCP support
InvoiceIn provides a hosted streamable HTTP MCP server with five read-only tools. A local stdio bridge mirrors those tools and forwards calls to the hosted server.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://invoicein-api.peculiar.systems/mcpclaude mcp add --transport http peculiar-systems-invoicein https://invoicein-api.peculiar.systems/mcp{"mcpServers":{"peculiar-systems-invoicein":{"type":"http","url":"https://invoicein-api.peculiar.systems/mcp"}}}Open in Cursor{"servers":{"peculiar-systems-invoicein":{"type":"http","url":"https://invoicein-api.peculiar.systems/mcp"}}}Open in VS Code{"mcpServers":{"peculiar-systems-invoicein":{"type":"http","url":"https://invoicein-api.peculiar.systems/mcp"}}}{"mcpServers":{"peculiar-systems-invoicein":{"serverUrl":"https://invoicein-api.peculiar.systems/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
https://invoicein-api.peculiar.systems/mcpAuth requiredTools
5| Parameter | Type | Required | Description |
|---|---|---|---|
| ksef | string | No | Poland only: the KSeF number the National e-Invoice System gave this invoice — 35 characters, NNNNNNNNNN-RRRRMMDD-FFFFFFFFFFFF-FF — or the collective identifier covering it (NNNNNNNNNN-IZRRRRMM-FFFFFFFFFFFF-FF). KSeF assigns it on acceptance, so it is never inside the FA(2)/FA(3) XML: it arrives beside the invoice in the KSeF API response, the UPO or the QR code on a visualisation. Pass it and it is checked against the invoice and returned on payment.ksef_number, the reference a Polish buyer must quote in the bank transfer title from 2027-01-01. Leave empty for invoices from any other country. |
| lang | enum | No | Language of the fix hints in the validation report and of the labels in HTML output. Default en.en | de | pl | it | fr |
| path | string | No | Absolute path of the invoice file on the machine running the server, used instead of file_base64. Only honoured over stdio (`python -m invoicein.mcp_server`); the hosted server at invoicein-api.peculiar.systems ignores it and answers with an error asking for file_base64. |
| file_base64 | string | No | Invoice file content, base64-encoded (standard alphabet). Accepted content: XML in UBL 2.1, CII D16B, XRechnung, Peppol BIS Billing 3, FatturaPA 1.2 or KSeF FA(2)/FA(3) syntax, or a ZUGFeRD 1.0/2.x or Factur-X hybrid PDF (the embedded XML is used). Max 25 MB decoded. Required unless `path` is given. |
Details
From the project READMEInvoiceIn — examples
Any European or UAE (PINT AE) e-invoice a business receives → one canonical EN 16931 JSON, a validation report with plain-language fix hints, a PDF, CSV or DATEV export. One stateless endpoint, nothing stored.
Accepts: XRechnung (UBL and CII), EN 16931 UBL 2.1 Invoice/CreditNote, Peppol BIS Billing 3, CII D16B, ZUGFeRD 1.0 / 2.x and Factur-X hybrid PDFs, Italy's FatturaPA 1.2, Poland's KSeF FA(2)/FA(3), Romania's RO e-Factura (CIUS-RO), the UAE's PINT AE (Billing and Self-Billing).
Validated against: EN 16931 validation artefacts 1.3.17, XRechnung 3.0.2 (KoSIT Schematron 2.6.0), Peppol BIS Billing 3, FNFE CTC-FR 1.4.0.04 (the BR-FR rules; runs when seller and buyer are both established in France), CIUS-RO 1.0.1, OpenPeppol's PINT AE 1.0.4 for the UAE (free check page: https://invoicein.peculiar.systems/uae), the UBL, CII, FatturaPA and KSeF schemas — plus arithmetic cross-checks on every format and market conventions no Schematron reads (German Skonto terms in free text, the Polish KSeF number). The live list with versions is at GET /v1/formats.
- Product page: https://invoicein.peculiar.systems (EN · DE · PL · IT · FR)
- API reference (interactive): https://invoicein-api.peculiar.systems/docs
- OpenAPI: https://invoicein-api.peculiar.systems/openapi.json
- Postman: public collection · published docs — or import
postman/InvoiceIn.postman_collection.json. Every request already carries a real XRechnung in its body, so Send works with no setup - MCP server:
https://invoicein-api.peculiar.systems/mcp(streamable HTTP) — on the official registry asio.github.peculiar-systems/invoiceinand on Smithery
This repository holds runnable examples, sample invoices you can test with, and the MCP registry manifest. The service itself is not open source.
Nothing you send is stored: the document is parsed in memory and the response is built from it. Privacy (full policy) · Terms
The bridge in bridge/ is a transparent proxy, not a second implementation: it mirrors whatever tools/list returns from the hosted server, so the two can never drift. The five tools and their annotations — all read-only, non-destructive, idempotent, closed-world — are in bridge/tools.json, checked by tests/. A static analyser reading the bridge source alone sees one dispatch callback and no tools; that is the proxy, not the tool surface.
60 seconds
curl -X POST "https://invoicein-api.peculiar.systems/v1/invoice?include=validation&lang=en" \
-H "X-Api-Key: $INVOICEIN_KEY" \
-F file=@samples/factur-x-en16931.pdf
No key yet? Leave the header out: 20 invoices a day per IP, same output. A trial key (100 invoices, 30 days, no card) comes from the product page.
The response (full example):
{
"ok": true,
"source": { "syntax": "UBL", "format": "peppol-bis3", "profile": "Peppol BIS Billing 3.0", "container": "xml" },
"invoice": { // canonical EN 16931, field names carry BT/BG numbers in /v1/schema
"document": { "id": "Snippet1", "issue_date": "2017-11-13", "type_code": "380", "currency": "EUR", "due_date": "2017-12-01", ... },
"seller": { "name": "SupplierOfficialName Ltd", "vat_id": "GB1232434", "electronic_address": { "value": "9482348239847239874", "scheme": "0088" }, ... },
"buyer": { ... },
"lines": [ { "id": "1", "quantity": 7, "unit": "DAY", "net_amount": 2800, "tax": { "category": "S", "rate": 25 }, "item": { "name": "item name" } }, ... ],
"tax_breakdown": [ { "taxable_amount": 1325, "tax_amount": 331.25, "category": "S", "rate": 25 } ],
"totals": { "line_net": 1300, "charges": 25, "net": 1325, "tax": 331.25, "gross": 1656.25, "due": 1656.25 },
"payment": { "means_code": "30", "remittance_info": "Snippet1", "credit_transfers": [ { "iban": "IBAN32423940", "account_name": "AccountName", "bic": "BIC324098" } ] }
},
"validation": { "valid": true, "errors": 0, "warnings": 0,
"rule_sets": [ { "id": "XSD:ubl-invoice" }, { "id": "EN16931-UBL", "version": "EN 16931 validation artefacts 1.3.17" }, { "id": "Peppol-UBL" } ],
"issues": [] },
"timings_ms": { "detect": 0.5, "map": 14.4, "validate": 86.0, "total": 100.8 },
"credits": { "mode": "key", "remaining": 99 }
}
When something is wrong, every failed rule carries a hint in the requested language (example, KSeF FA(3) in Polish):
{ "id": "XSD-UNEXPECTED-ELEMENT", "severity": "error", "rule_set": "XSD:fa3",
"message": "Element '{http://crd.gov.pl/wzor/2025/06/25/13775/}Adnotacje': This element is not expected. Expected is one of ( {http://crd.gov.pl/wzor/2025/06/25/1 …",
"hint": "XML zawiera element, którego schemat nie dopuszcza w tym miejscu. Nazwa elementu jest błędna, element należy do innego profilu/wersji (np. UBL 2.0 lub ZUGFeRD EXTENDED), jest zdublowany albo jest własnym rozszerzeniem. Usuń go lub zmień jego nazwę.",
"who": "sender", "location": "/*/*[4]/*[8]", "line": 43 }
Endpoints
| Call | Returns |
|---|---|
POST /v1/invoice?include=validation,html,pdf,csv,datev&lang=en|de|pl|it|fr | everything in one JSON (extras base64/inline) |
POST /v1/parse | canonical JSON only |
POST /v1/validate | validation report only |
POST /v1/render.html · POST /v1/render.pdf | human-readable rendering, labels in the five languages |
POST /v1/export.csv?level=lines|documents | flat CSV |
POST /v1/export.datev?skr=03|04&creditor_account=70000 | DATEV Buchungsstapel (EXTF 700, cp1252) |
GET /v1/formats · GET /v1/rules/{id}?lang=de · GET /v1/schema | formats + rule versions · explain a rule id · field guide |
GET /v1/countries | which format each country's mandate asks for, and what we validate it with |
GET /v1/vat/{number} | EU VAT number: format offline, then live VIES, with a dated receipt |
GET /v1/peppol/{id} | is a counterparty published on Peppol, and what can it receive |
Body: multipart field file, or the raw XML/PDF. Send a real User-Agent (Cloudflare rejects the default Python-urllib one with error 1010). Auth: X-Api-Key or Authorization: Bearer. One invoice = one credit whatever outputs you request; a file that carries several invoices (a FatturaPA lot) costs one per invoice. Remaining credits come back in X-Credits-Remaining.
Examples in this repo
examples/curl.sh— every endpoint onceexamples/node.mjs—fetch+FormData, no dependenciesexamples/python.py— standard library onlyexamples/n8n-workflow.json— mailbox attachment → InvoiceIn → JSON, importable into n8nmcp/server.json— manifest for the MCP registry;mcp/clients.md— Claude Desktop / Cursor configbridge/invoicein_mcp_bridge.py— local stdio MCP server that mirrors the hosted server's tools one-to-one and forwards every call (for clients without remote support;Dockerfilebuilds it;bridge/tools.jsonis the offline copy of the tool definitions)
Sample invoices
| File | What it is | Source / licence |
|---|---|---|
samples/xrechnung-3.0-ubl.xml, samples/xrechnung-3.0-cii.xml | the same XRechnung 3.0 invoice in both syntaxes | KoSIT XRechnung testsuite, Apache-2.0 |
samples/peppol-bis3-base-example.xml | Peppol BIS Billing 3 base example | OpenPeppol, Apache-2.0 |
samples/factur-x-en16931.pdf | Factur-X hybrid PDF, EN 16931 profile | ZUGFeRD corpus (FNFE-MPE examples), Apache-2.0 |
samples/ksef-fa3-przyklad-1.xml | KSeF FA(3) official example no. 1 | Polish Ministry of Finance, public |
samples/fatturapa-fpr01.xml | FatturaPA 1.2 official example FPR01 | Agenzia delle Entrate, public |
Both XRechnung files produce the same canonical JSON (only the syntax-specific extensions block differs) — that is the point of the canonical model.
What it does not do
No OCR (a PDF without embedded XML is rejected with pdf-no-xml). Not a Peppol access point, not a French PDP, not a UAE Accredited Service Provider, not a KSeF or SdI client: it reads what you already received and never transmits an invoice anywhere. Factur-X/ZUGFeRD profiles below EN 16931 (MINIMUM, BASIC WL, BASIC) get schema and arithmetic checks only, because the EN 16931 rules would only produce noise there. Validation results are informational, not legal advice.
Licence
The examples in this repository are MIT. Sample invoices keep the licences listed above.
Comments
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