MCP Server
invowerk
dev.invowerk/invowerk
What this MCP does
Parses, generates, converts, validates, renders, and explains structured electronic invoices including EN 16931, XRechnung, ZUGFeRD, Factur-X, and Peppol formats.
Capabilities
Tools
6
tools
convert_invoice
Convert an e-invoice between UBL and CII
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`, `flavor` and `self_validation` (`valid`,
`finding_count`). invowerk checks the converted XML before answering and never
returns an invalid document. Input that cannot be read or converted fails with
an error message.
Credits: 3 per call.
Read only
Open world
Input schema
{'type': 'object', 'required': ['target_syntax'], 'properties': {'file': {'type': 'object', 'default': None, 'required': ['download_url', 'file_id'], 'properties': {'file_id': {'type': 'string', 'description': 'An identifier for the file. ChatGPT sets it; other clients may pass any label, such as the file name.'}, 'file_name': {'type': 'string'}, 'mime_type': {'type': 'string'}, 'download_url': {'type': 'string', 'description': 'A public https URL of the file.'}}, 'description': "The file as a download link, instead of `invoice_base64`. In ChatGPT, pass the user's uploaded file here. Other clients can set `download_url` to a public https URL."}, 'target_flavor': {'anyOf': [{'type': 'string'}, {'type': 'null'}], 'default': None, 'description': 'Optional: "en16931" or "xrechnung". Without it the flavor of the source is kept.'}, 'target_syntax': {'type': 'string', 'description': 'Syntax to convert to: "ubl" or "cii".'}, 'invoice_base64': {'anyOf': [{'type': 'string'}, {'type': 'null'}], 'default': None, 'description': 'The invoice file, base64-encoded. At most 4 MB decoded.'}}, 'additionalProperties': False}
Output schema
{'type': 'object', 'additionalProperties': True}
explain_errors
Explain error codes
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`, `meaning`,
`causes`, `fixes`, `severity`, `standard`, `bt_refs`, `xpath_hints` and
`explain_url` (the German page for the code). If any code is unknown, the call
fails and names the unknown codes.
Credits: free. This tool is not metered.
Read only
Input schema
{'type': 'object', 'required': ['codes'], 'properties': {'lang': {'type': 'string', 'default': 'de', 'description': 'Language of the explanations: "de" (default) or "en".'}, 'codes': {'type': 'array', 'items': {'type': 'string'}, 'description': 'One or more rule codes from validate_invoice, e.g. ["BR-CO-18", "BR-DE-21"].'}}, 'additionalProperties': False}
Output schema
{'type': 'object', 'additionalProperties': True}
generate_invoice
Create an e-invoice from JSON
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), `invoice_number`,
`issue_date` (YYYY-MM-DD), `currency`, `seller`, `buyer`, `lines`,
`tax_breakdown`, `totals`. invowerk writes your amounts as given. It does not
compute or correct them.
Returns `xml`, `syntax`, `flavor` and `self_validation`. invowerk checks the
XML before answering and never returns an invalid document. Invalid input, or
XML that fails the check, returns an error.
Credits: 5 per call.
Read only
Input schema
{'type': 'object', 'required': ['invoice'], 'properties': {'invoice': {'type': 'object', 'description': "The invoice as a JSON object keyed on EN 16931 Business Terms, the schema of POST /v1/generate and of parse_invoice's `model`: syntax, flavor, invoice_number, issue_date, currency, seller, buyer, lines, tax_breakdown, totals.", 'additionalProperties': True}}, 'additionalProperties': False}
Output schema
{'type': 'object', 'additionalProperties': True}
parse_invoice
Read an e-invoice into JSON
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.
Returns `model` (the invoice as JSON), `detection` (`syntax`, `flavor`,
`customization_id`) and `source` ("xml" or "pdf-embedded"). A file that cannot
be read fails with an error that starts with an error code, e.g. a PDF without
embedded XML, a UBL credit note or malformed XML.
Credits: 2 per call.
Read only
Open world
Input schema
{'type': 'object', 'properties': {'file': {'type': 'object', 'default': None, 'required': ['download_url', 'file_id'], 'properties': {'file_id': {'type': 'string', 'description': 'An identifier for the file. ChatGPT sets it; other clients may pass any label, such as the file name.'}, 'file_name': {'type': 'string'}, 'mime_type': {'type': 'string'}, 'download_url': {'type': 'string', 'description': 'A public https URL of the file.'}}, 'description': "The file as a download link, instead of `invoice_base64`. In ChatGPT, pass the user's uploaded file here. Other clients can set `download_url` to a public https URL."}, 'invoice_base64': {'anyOf': [{'type': 'string'}, {'type': 'null'}], 'default': None, 'description': 'The invoice file, base64-encoded. At most 4 MB decoded.'}}, 'additionalProperties': False}
Output schema
{'type': 'object', 'additionalProperties': True}
render_invoice
Render an e-invoice as HTML
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 complete HTML document), `lang`, `flavor` (e.g.
"xrechnung") and `syntax` (e.g. "ubl_invoice"). A file that is not an XML
invoice, malformed XML or XML with a DOCTYPE fails with an error message.
Credits: 1 per call.
Read only
Open world
Input schema
{'type': 'object', 'properties': {'file': {'type': 'object', 'default': None, 'required': ['download_url', 'file_id'], 'properties': {'file_id': {'type': 'string', 'description': 'An identifier for the file. ChatGPT sets it; other clients may pass any label, such as the file name.'}, 'file_name': {'type': 'string'}, 'mime_type': {'type': 'string'}, 'download_url': {'type': 'string', 'description': 'A public https URL of the file.'}}, 'description': "The file as a download link, instead of `invoice_base64`. In ChatGPT, pass the user's uploaded file here. Other clients can set `download_url` to a public https URL."}, 'lang': {'type': 'string', 'default': 'de', 'description': 'Language of the labels: "de" (default) or "en".'}, 'invoice_base64': {'anyOf': [{'type': 'string'}, {'type': 'null'}], 'default': None, 'description': 'The invoice file, base64-encoded. At most 4 MB decoded.'}}, 'additionalProperties': False}
Output schema
{'type': 'object', 'additionalProperties': True}
validate_invoice
Check an e-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
unreachable, invowerk's own check with the same rules decides,
`verdict_source` is "local" and `official_degraded` is true.
`disagreement` is true when both ran and differ. `findings` lists each
problem with `rule_id`, `severity` and `message`; pass the codes to
`explain_errors` (free). `pdfa_verdict` is the PDF/A check of a PDF.
`hints` never change `valid`. Unreadable input returns a finding, not an
error.
Credits: 1 per call.
Read only
Open world
Input schema
{'type': 'object', 'properties': {'file': {'type': 'object', 'default': None, 'required': ['download_url', 'file_id'], 'properties': {'file_id': {'type': 'string', 'description': 'An identifier for the file. ChatGPT sets it; other clients may pass any label, such as the file name.'}, 'file_name': {'type': 'string'}, 'mime_type': {'type': 'string'}, 'download_url': {'type': 'string', 'description': 'A public https URL of the file.'}}, 'description': "The file as a download link, instead of `invoice_base64`. In ChatGPT, pass the user's uploaded file here. Other clients can set `download_url` to a public https URL."}, 'lang': {'type': 'string', 'default': 'de', 'description': 'Language of the explanations: "de" (default) or "en".'}, 'explain': {'type': 'boolean', 'default': False, 'description': 'true adds an explanation to each finding whose rule has one.'}, 'invoice_base64': {'anyOf': [{'type': 'string'}, {'type': 'null'}], 'default': None, 'description': 'The invoice file, base64-encoded. At most 4 MB decoded.'}}, 'additionalProperties': False}
Output schema
{'type': 'object', 'additionalProperties': True}
History
Recent tool changes
Added
convert_invoice
Sept. 29, 2026, 2:40 a.m.
Added
parse_invoice
Sept. 29, 2026, 2:40 a.m.
Added
generate_invoice
Sept. 29, 2026, 2:40 a.m.
Added
explain_errors
Sept. 29, 2026, 2:40 a.m.
Added
render_invoice
Sept. 29, 2026, 2:40 a.m.
Added
validate_invoice
Sept. 29, 2026, 2:40 a.m.
Discover
Similar MCP servers
BeeL
es.beel/mcp
Provides Spanish company administration and VeriFactu-compliant invoicing, including customers, products, invoice issuance, corre…
corply
io.github.corply-dev/corply
Supports company formation and corporate administration including incorporation documents, signatures, cap tables, corporate acti…
RESET Verifica
com.resetparatodos/verifica
Verifies Mexican businesses, invoices, payments, identities, tax and labor calculations, legal texts, sanctions and PEP lists, ba…
eu-verify
io.github.contentfactory/eu-verify
Verifies European companies, registries, VAT, EORI, LEI, sanctions, insolvency, financial filings, IBANs, emails, addresses, and …
Israel Business Intelligence MCP
io.github.itzikhr18/israel-business-intelligence
Provides Israeli company identity previews, registry-based verification workflows, invoice checks, and payment-risk decision prev…
Lovie Company Formation
co.lovie/company-formation
Supports company formation and business administration with bank accounts, cards, invoicing, bookkeeping, accounting periods, and…
AgentLot Marketplace
io.agentlot/marketplace
Enables agents and users to discover, bid on, purchase, deliver, and settle paid digital services and compute work.
DPX — Institutional Cross-Border Settlement
io.github.untitledfinancial/dpx
Provides compliance-gated cross-border crypto settlement, agent registration and spending mandates, stablecoin routing, ESG and s…