contix MCP servers

Remote MCP servers by contix, Spanish invoicing software with Veri*factu. Both are hosted; there is nothing to install. This repository holds only the public metadata (the server code is not open source).

1. contix herramientas (free, no account, no auth)

https://api.contix.es/api/v1/mcp/herramientas

Streamable HTTP, no authentication. Four read-only tools:

Tool	What it does
`validate_iban`	IBAN check: country length and ISO 13616 check digits; for Spanish IBANs also the account check digits (DC) and the bank with its BIC (Banco de España registry). A 20-digit Spanish account number is converted to its IBAN.
`check_vat_number`	Looks up an EU VAT number in the European Commission's VIES registry and returns what the registry says.
`calculate_modelo_303`	Sums the boxes of the Spanish quarterly VAT return (Modelo 303) with the formulas of the official AEAT form.
`get_obligation_dates`	Veri*factu and mandatory B2B e-invoicing dates in Spain from the published rules.

Results are arithmetic or registry facts, never tax advice. The same tools are a plain REST API without key: https://api.contix.es/api/v1/herramientas (docs). In the browser: contix.es/herramientas.

2. contix (invoicing, needs a contix account)

https://api.contix.es/api/v1/mcp

Streamable HTTP, OAuth 2.1 (dynamic client registration + PKCE) or API key. About 60 tools to run Spanish invoicing from your AI assistant: customers, draft invoices, finalizing into the Veri*factu hash chain (asks for explicit confirmation), payments, expenses, recurring invoices, quotes, Facturae/FACe and Modelo 303/349/390 figures. Read-only and write scopes.

Setup for Claude, ChatGPT and Cursor: contix.es/mcp · API reference: contix.es/api · OpenAPI: https://api.contix.es/openapi.json

Configuration

Clients that take a JSON config:

{
  "mcpServers": {
    "contix-herramientas": { "type": "http", "url": "https://api.contix.es/api/v1/mcp/herramientas" },
    "contix": { "type": "http", "url": "https://api.contix.es/api/v1/mcp" }
  }
}

Registry

Both servers are in the Official MCP Registry as es.contix/herramientas and es.contix/contix (server.json files here are copies).

Contact

[email protected] · Privacy · Terms

contix is software that issues invoices, not a tax advisory service.

contix MCP servers