invowerk
E-invoice checker for ZUGFeRD, Factur-X, XRechnung and Peppol BIS. Free web tool, API and MCP.
| Endpoint | https://api.invowerk.dev/mcp/ (streamable-http) |
|---|---|
| Registry version | 1.0.1 |
| Now | 6 tools · grade A (98) · pin ts_428a18945f2cf8a53f7df0792ab553ed · protocol 2025-06-18 |
| First / last listed | 2026-10-25 02:23 UTC / 2026-10-25 02:23 UTC |
| Grade over time | 2026-10-25: A (98), 6 tools |
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Tools: validate_invoice render_invoice explain_errors generate_invoice parse_invoice convert_invoice
validate_invoice | Check an e-invoice against EN 16931 and German rules.
Input: `invoice_base64` is the base64 of an XML invoice (UBL or CII) or a
ZUGFeRD / Factur-X PDF, at most 4 MB decoded; or pass the file as a download
link in `file`. `explain=true` adds an explanation to findings whose rule
has one, in `lang` ("de" or "en").
`valid` is the result. For XRechnung the KoSIT validator decides. If it is
unreachab params: invoice_base64, file, explain, lang |
render_invoice | Render an XML e-invoice (UBL or CII, e.g. XRechnung) as a readable HTML page.
invowerk uses the KoSIT XRechnung visualization. Use it to show a person what
an e-invoice contains.
Input: `invoice_base64` is the base64 of the XML, at most 4 MB decoded, or pass
the file as a download link in `file`. PDFs are not accepted. `lang` sets the
label language, "de" (default) or "en".
Returns `html` (a co params: invoice_base64, file, lang |
explain_errors | Explain rule codes in plain language. Works without an API key.
Covers the codes of `validate_invoice` findings and hints: EN 16931,
XRechnung, ZUGFeRD and invowerk's own hint codes (IW-*).
Input: `codes` is a list of one or more codes, e.g. ["BR-CO-18", "BR-DE-21"].
Duplicates are removed. `lang` is "de" (default) or "en".
Returns `lang` and `explanations`. Each explanation has `title`, `meani params: codes*, lang |
generate_invoice | Create a valid EN 16931 e-invoice (UBL or CII XML) from JSON.
Input: `invoice` is a JSON object keyed on EN 16931 Business Terms, the same
schema as `POST /v1/generate`, at most 4 MB. Main fields: `syntax` ("ubl"
default, or "cii"), `flavor` ("en16931" default, or "xrechnung", which
requires `buyer_reference`, the Leitweg-ID BT-10, and `payment_iban`),
`invoice_number`,
`issue_date` (YYYY-MM-DD), params: invoice* |
parse_invoice | Read an existing e-invoice into JSON keyed on EN 16931 Business Terms.
The JSON is the input format of `generate_invoice`, so you can edit it and
create the invoice again.
Input: `invoice_base64` is the base64 of an XML invoice (UBL or CII) or a
ZUGFeRD / Factur-X PDF, at most 4 MB decoded; or pass the file as a download
link in `file`. A PDF may have at most 500 pages and 16 attachments.
Retur params: invoice_base64, file |
convert_invoice | Convert an e-invoice to UBL or CII. The result is checked before it is returned.
Input: `invoice_base64` is the base64 of an XML invoice or a ZUGFeRD /
Factur-X PDF, at most 4 MB decoded; or pass the file as a download link in
`file`. `target_syntax` is "ubl" or "cii". `target_flavor` is optional,
"en16931" or "xrechnung"; without it the flavor of the source is kept.
Returns `xml`, `syntax`, `fl params: target_syntax*, invoice_base64, file, target_flavor |
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