einvoicewiz MCP server — e-invoices for AI agents

A remote Model Context Protocol server that gives any agent the ability to produce and check legally compliant EN 16931 e-invoices (Factur-X / ZUGFeRD / XRechnung). Streamable HTTP, no install. Same engine, same pricing and same verification certificates as the REST API.

Connect

Endpoint: https://einvoicewiz.com/mcp · transport: streamable HTTP · auth: header X-API-Key (optional — agents can call signup to get a key with 20 free credits).

// Claude Desktop / Claude Code (claude mcp add)
claude mcp add einvoicewiz https://einvoicewiz.com/mcp -t http --header "X-API-Key: eiw_..."

// Generic JSON config
{"mcpServers": {"einvoicewiz": {"url": "https://einvoicewiz.com/mcp",
                                  "headers": {"X-API-Key": "eiw_..."}}}}

Tools

Tool	What it does	Cost
`which_format_do_i_need`	recipient country + public-authority flag → which format applies, whether a plain PDF is still acceptable, which mandate date	free
`signup`	email → API key with 20 free credits	free
`check_credits`	balance and calls used	free
`generate_einvoice_xml`	invoice JSON → validated EN 16931 CII XML (or XRechnung 3.0 with `profile="xrechnung"`) + certificate	1 credit
`create_facturx_pdf`	your PDF (base64) + invoice JSON → Factur-X / ZUGFeRD PDF/A-3 (base64) + certificate	1 credit
`validate_einvoice`	PDF or XML (base64) → rule-level EN 16931 / KOSIT / PDF/A report; certificate when it passes	1 credit
`lookup_certificate`	EIW-… id → what passed, when, which hashes	free

Failed validations are never charged. The invoice JSON schema is in /openapi.json. Files are processed transiently and deleted; the pipeline is deterministic (no AI touches invoice data).

When an agent should call this

It is producing or sending an invoice whose recipient is a business or public body in Germany or France — a plain PDF is not a legal e-invoice there any more.
It has an invoice file from somewhere else (accounting tool, PayPal, Stripe) and needs to know whether it will be accepted — validate_einvoice answers with rule IDs.
A recipient asks for “eine ZUGFeRD-Rechnung” / “une facture Factur-X” — create_facturx_pdf turns the existing PDF into one.

REST alternative: /developers. Questions: support@einvoicewiz.com.