# Validate EU VAT Numbers in Claude Desktop, Cursor, and ChatGPT — Official MCP Server

> Source: <https://dev.to/iurii_rogulia/validate-eu-vat-numbers-in-claude-desktop-cursor-and-chatgpt-official-mcp-server-509d>
> Published: 2026-05-27 09:00:33+00:00

Originally published at

[vatnode.dev]. The version on vatnode.dev is the canonical source — refer to it for the latest content.

Your AI assistant can now check if a VAT number is real, pull the registered company name, and look up VAT rates for every EU country — all without leaving the chat. We just released [ vatnode-mcp](https://www.npmjs.com/package/vatnode-mcp), the official Model Context Protocol (MCP) server for vatnode.

This post covers what MCP is in 30 seconds, how to install the vatnode server in Claude Desktop / Cursor / ChatGPT, and a few concrete examples of why this is useful for anyone doing EU B2B work.

[Model Context Protocol](https://modelcontextprotocol.io) is an open standard from Anthropic for connecting AI assistants to external tools and data sources. An MCP server exposes a small set of *tools* — named functions with described inputs — and the AI model picks the right one based on what the user is asking.

Think of it as the "USB-C of AI integrations": write one MCP server and any compatible client (Claude Desktop, Cursor, ChatGPT's custom-connectors, Cline, Continue, and more) can use it. The user just edits a config file once — no per-app integration work.

`vatnode-mcp`

ships five tools, four of them fully offline and free:

`get_country_vat_rates`

`list_eu_vat_rates`

`check_vat_format`

`list_supported_countries`

`validate_vat_number`

Why four free tools? Because the data is bundled into the package via [eu-vat-rates-data](https://www.npmjs.com/package/eu-vat-rates-data) (also open source) — there's nothing to charge for. The paid tool is the one that calls real VIES infrastructure.

One config file edit. Open `claude_desktop_config.json`

(on macOS: `~/Library/Application Support/Claude/`

) and add:

```
{
  "mcpServers": {
    "vatnode": {
      "command": "npx",
      "args": ["-y", "vatnode-mcp"],
      "env": {
        "VATNODE_API_KEY": "vat_live_..."
      }
    }
  }
}
```

Restart Claude Desktop. That's it. The vatnode tools appear in the tool picker. For Cursor, paste the same JSON in **Settings → MCP → Add new server**. ChatGPT custom connectors and other MCP clients (Continue, Cline) follow the same pattern.

The `VATNODE_API_KEY`

is optional — without it you still get all four free tools. To enable live VIES validation, [grab a free API key](https://vatnode.dev/register) (no credit card; the free tier includes a monthly request quota).

A few real example exchanges (you don't have to name the tool — Claude picks it from the description):

You:What's the standard VAT rate in Finland and Germany?

(Claude calls`get_country_vat_rates`

for FI and DE — free, no key needed.)

Claude:Finland's standard VAT rate is 25.5% (raised from 24% in September 2024). Germany's is 19%. Finland also has reduced rates of 13.5% and 10%; Germany has 7%.

You:Is IE6388047V a valid VAT?

(Claude calls`validate_vat_number`

— uses your API key.)

Claude:Yes, IE6388047V is valid. It belongs toGOOGLE IRELAND LIMITED, registered at Gordon House, Barrow Street, Dublin 4, Ireland.

You:I have a list of 12 European customers. Tell me which countries have reduced VAT rates for restaurant services.

(Claude calls`list_eu_vat_rates`

, processes the result and answers in context.)

Claude:France (10% reduced), Spain (10%), Italy (10%), Portugal (13% intermediate)... [the model interprets the data for the user's actual question]

The point isn't that Claude does VAT lookup faster than a Google search. It's that the result lands in the same conversation where you're drafting an invoice, double-checking a supplier, or writing checkout code — no context switch.

Third-party MCP marketplaces sometimes ship VAT-validation wrappers built around our public API. Using `vatnode-mcp`

directly is the only way to:

The current release ships five tools. Coming soon: `bulk_validate`

for processing lists in one call, `subscribe_to_vat_changes`

for monitoring (so the agent can warn you if a known-good VAT later de-registers), and a `vies_consultation_number`

tool that returns the audit token VIES issues when a requester VAT is configured.

If you have a specific use case the current tools don't cover, open an issue on [GitHub](https://github.com/vatnode/vatnode-mcp/issues) — tool descriptions are tuned based on what people actually try, so feedback directly shapes the next release.

## Try it now

[Sign up]for a free vatnode account (optional — needed only for live VIES validation)- Paste the config block above into your
`claude_desktop_config.json`

- Restart Claude Desktop and ask it a VAT question
Full docs:

[vatnode.dev/docs/mcp]