About Vat
Vat is an MCP server that checks VAT registration number formats for EU countries, the UK, Switzerland, and Norway. It works offline without a key and checks format only, not registration status.
Key features
- 01Validate VAT number format
- 02List supported countries and formats
Use cases
- 01Check a VAT number's country-specific format
- 02Find the expected VAT format for a country
MCP support
Exposes VAT format validation and supported-format lookup tools to MCP clients through a Pipeworx endpoint or standalone local stdio server. The gateway endpoint also includes shared Pipeworx meta-tools.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://gateway.pipeworx.io/vat/mcpclaude mcp add --transport http pipeworx-io-vat https://gateway.pipeworx.io/vat/mcp{"mcpServers":{"pipeworx-io-vat":{"type":"http","url":"https://gateway.pipeworx.io/vat/mcp"}}}Open in Cursor{"servers":{"pipeworx-io-vat":{"type":"http","url":"https://gateway.pipeworx.io/vat/mcp"}}}Open in VS Code{"mcpServers":{"pipeworx-io-vat":{"type":"http","url":"https://gateway.pipeworx.io/vat/mcp"}}}{"mcpServers":{"pipeworx-io-vat":{"serverUrl":"https://gateway.pipeworx.io/vat/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
Details
From the project READMEmcp-vat
VAT-number format validation MCP (EU + UK/CH/NO).
Part of Pipeworx — an MCP gateway connecting AI agents to 1679+ live data sources.
Tools
| Tool | Description |
|---|---|
validate_vat | Validate the FORMAT of a VAT registration number for the EU (+ UK/CH/NO), keyless & offline. Accepts the number with its country prefix ("DE123456789") or a national number plus country. Returns whether it matches the official country pattern. NOTE: format only — it does NOT confirm the VAT number is registered/active (use the EU VIES service for that). |
list_vat_formats | List the supported countries and their VAT-number formats. |
Quick Start
Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):
{
"mcpServers": {
"vat": {
"url": "https://gateway.pipeworx.io/vat/mcp"
}
}
}
What this endpoint actually serves
tools/list at https://gateway.pipeworx.io/vat/mcp returns the tools in the table
above plus the shared Pipeworx meta-tools — ask_pipeworx,
discover_tools, search_within, remember/recall and the rest of the
gateway-wide set. So the tool count you see is larger than this table: a
single-pack endpoint currently lists roughly 30 shared tools alongside the
pack's own. The connection's initialize response states its exact scope, and
is the authoritative answer for a given day.
This is deliberate, not multiplexing by accident. The meta-tools are what let a
scoped connection answer a question this pack does not cover — via
ask_pipeworx, which routes across the whole catalog — without you adding a
second MCP server. There is currently no way to mount a pack endpoint without
them; if the extra schemas cost you more context than the routing is worth,
connect to the full gateway once rather than to several pack endpoints.
Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:
{
"mcpServers": {
"pipeworx": {
"url": "https://gateway.pipeworx.io/mcp"
}
}
}
Both URLs reach the same gateway and the same 1679+ data sources. The
only difference is which pack's tools are listed directly; ask_pipeworx
reaches all of them from either one.
No MCP client? Call it over HTTP
curl -X POST https://gateway.pipeworx.io/v1/tools/validate_vat \
-H 'Content-Type: application/json' \
-d '{"vat":"DE123456789"}'
No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/validate_vat. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.
Standalone (no gateway account)
This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:
{
"mcpServers": {
"vat": {
"command": "npx",
"args": ["-y", "@pipeworx/mcp-vat"]
}
}
}
Or run it directly to confirm it starts:
npx -y @pipeworx/mcp-vat
It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call
for only this pack's tools — none of the shared meta-tools the gateway
connection above adds. Same source, same tools, no ask_pipeworx routing.
Using with ask_pipeworx
Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:
ask_pipeworx({ question: "your question about Vat data" })
The gateway picks the right tool and fills the arguments automatically.
More
License
MIT
Comments
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