EU Business Check in Claude
VAT numbers, LEIs, registries. The MCP server is https://eubusiness.openkrill.app/mcp. No key. The steps below are only for Claude. A call to check_vat_number was checked against that server on 2026-10-01.
What this server answers
Check a European business before you pay or sign. Ask "is DE 811128135 a valid VAT number?", "what is the LEI of Siemens AG?" or "find the registered company called Equinor in Norway".
EU Business Check asks the official sources directly: the European Commission's VIES service for VAT numbers, the GLEIF Global LEI Index for Legal Entity Identifiers, and two national registers, the French Sirene register (through the api.gouv.fr company search) and the Norwegian Enhetsregisteret.
A VAT check says whether a number is registered for VAT in an EU member state or Northern Ireland on the day of the check. When the registered name and address are published they are shown, but only for legal entities: a name without a legal-form marker such as GmbH, SA, SRL or Limited could be a private person, so it is withheld. Some countries, such as Germany and Spain, do not publish a name at all. If you give your own VAT number, VIES also issues a consultation number that proves the check was made.
LEI and registry results show the legal name, status, legal form, registration number, address and, where published, activity and size. Sole proprietors are left out of every result because they are registered under a private person's name.
It reads only these public registers. It does not rate a company's credit, solvency or reputation, does not cover other countries' registers, and a register can lag behind a change by days. Always check an important detail on the register itself.
It stores nothing about you: answers are cached for up to an hour, except a check that asks for a consultation number, and the only lasting record is a daily count of calls per tool.
What it can do
- Checks whether an EU or Northern Ireland VAT number is valid and shows the name of a legal entity
- Issues a VIES consultation number when given the requester's own VAT number
- Finds the Legal Entity Identifier (LEI) of a company by name, or looks a LEI up
- Searches the French (Sirene) and Norwegian company registers by name or number
- Leaves out sole proprietors and withholds names that could be a private person
Tools
check_vat_number, Check an EU VAT number. Use this when the user asks whether a VAT number is valid or whom it belongs to, for example "is DE 811128135 a valid VAT number?", "check the VAT number on this invoice, ATU33864707" or "I need a VIES consultation number for this supplier". Pass the country code and the VAT number, and requesterCountry with requesterVatNumber only when the user gives their own VAT number for a consultation number. Returns whether the number is registered for VAT on the date of the check and, for a legal entity where the member state publishes it, the registered name and address; a name that could be a private person is withheld. Covers EU member states and Northern Ireland (XI), not GB. Do not use it for a person's tax or identity checks, for VAT rates, or to judge whether a business is trustworthy.find_company_lei, Find a company's LEI. Use this when the user asks for the Legal Entity Identifier (LEI) of a company or wants to look up a LEI, for example "what is the LEI of Siemens AG?", "whose LEI is W38RGI023J3WT1HWRP32?" or "is the LEI of this German company still active?". Pass the company name (and a country code to narrow it) or the 20-character LEI. Returns each entity's LEI, legal name, status, legal form code, country and city, national registration number and the LEI's renewal dates. Sole proprietors are left out. Do not use it to find a private person, for companies that have no LEI (most small businesses), or for financial or credit information.lookup_company_registry, Look up a French or Norwegian company. Use this when the user asks about a company registered in France or Norway, for example "find the French company Danone", "who is behind SIREN 552032534?" or "look up Equinor in the Norwegian business register". Pass country FR or NO and the company name or its registration number (SIREN for France, organisation number for Norway). Returns the legal name, registration number, legal form, status (active, ceased, bankrupt, being wound up), registration date, registered address, activity code and, where published, size or employee count. Sole proprietors are left out. Do not use it for other countries, for owners, directors or any private person, or for accounts and credit ratings.
Add EU Business Check in Claude
Claude connects to a remote MCP server as a custom connector. The connection is made from Anthropic's cloud, not from your laptop, so the server must be on the public internet. EU Business Check is. These steps were checked against Claude's custom-connector article (updated 2026-08-11) and the Claude Code MCP docs on 2026-10-01.
On a Pro or Max plan:
- Open Customize, then Connectors.
- Select the plus button, then Add custom connector.
- Paste
https://eubusiness.openkrill.app/mcp. Leave Advanced settings empty: this server does not need an OAuth client id or secret. - Select Add. The connector is yours. Anthropic has not reviewed it, and it is not a Directory listing.
- In a conversation, open the plus button, then Connectors, and enable EU Business Check. Ask: Is the Austrian VAT number ATU33864707 valid, and who is it registered to?
On Team and Enterprise, an Owner adds the connector first at Organization settings, then Connectors, then Add, then Custom, then Web, and pastes the same URL. Members then connect it from Customize. A Free plan can add one custom connector.
In Claude Code, add it from the project directory:
claude mcp add --transport http eu-business https://eubusiness.openkrill.app/mcpThat writes a local or user config. A JSON entry needs "type": "http" (or streamable-http) plus the url. An entry with a url and no type is skipped. Confirm with claude mcp get eu-business. The tools you should see are check_vat_number, find_company_lei, lookup_company_registry.
Enable the connector only in conversations that need it. Claude can call the tools while you work, including during research, so turn off any tool you do not want invoked. EU Business Check does not write to your accounts. It still receives the arguments of each call. Read the privacy page before you paste anything that is not public.
A call checked on 2026-10-01
ATU33864707 is the public example in the plugin's starter prompts. No requester VAT number is sent. The request below was posted to https://eubusiness.openkrill.app/mcp as tools/call. HTTP 200. Source: the EU Business Check server, read 2026-10-01.
{
"method": "tools/call",
"params": {
"name": "check_vat_number",
"arguments": {
"country": "AT",
"vatNumber": "U33864707"
}
}
}- source. European Commission VIES (VAT Information Exchange System)
- country. AT
- name. Red Bull GmbH
- notice. A valid result means the number is registered for VAT in that member state, as the member state's own register reports it on the date shown. It does not say the business is trustworthy, solvent or the one a person is dea
Repeat the call yourself if you need a newer reading. Cached answers expire. A rate limit is not a result: wait and try again. Nothing in the call is a ranking, a filing, or advice.