Ares Cz

Official registry Government and legal

Czech business register (ARES) — look up any Czech company or sole trader by IČO or by name, from…

What can you do with Ares Cz?

  • ares_lookup_ico({ ico }) — one economic subject by its 8-digit IČO:
  • ares_search_name({ name, limit, offset, onlyActive }) — subjects whose

Install

Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).

Remote (streamable-http)
Claude Code
claude mcp add --transport http ares-cz 'https://gateway.pipeworx.io/ares-cz/mcp'
JSON configuration (Claude Desktop, Cursor, VS Code)
{
    "mcpServers": {
        "ares-cz": {
            "type": "http",
            "url": "https://gateway.pipeworx.io/ares-cz/mcp"
        }
    }
}

Documentation

From the project's README on GitHub, refreshed weekly. Links open on GitHub.

Contents
  1. @pipeworx/ares-cz
  2. Tools
  3. Auth
  4. Data sources
  5. Traps
  6. Quick Start
  7. No MCP client? Call it over HTTP
  8. Standalone (no gateway account)
  9. Using with ask_pipeworx
  10. More
  11. License

@pipeworx/ares-cz

Czech business register (ARES) — look up any Czech company or sole trader by IČO or by name, from the Ministry of Finance's official register of economic subjects.

Part of Pipeworx — an MCP gateway connecting AI agents to 1872+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

  • ares_lookup_ico({ ico }) — one economic subject by its 8-digit IČO: registered trading name, legal form, seat address, founding date, dissolution date, DIČ (VAT) number, CZ-NACE activity codes.
  • ares_search_name({ name, limit, offset, onlyActive }) — subjects whose trading name matches, with the total match count so a precise hit is distinguishable from a common word.

Auth

Keyless. No registration, no header, no quota documented.

Data sources

ARES is the Ministry of Finance's consolidated view over the commercial register (OR), the trade register (RŽP), the statistical register (RES) and the VAT payer register — so one IČO answers questions that would otherwise need three lookups.

Traps

  • IČO must be zero-padded to 8 digits on the REST path. "177041" 404s, "00177041" resolves; the pack pads for you.
  • A dissolved company still resolves. active is derived from whether datumZaniku is present, not from the lookup succeeding — treating a 200 as "still trading" is wrong.
  • pocet (page size) caps at 200 and a larger value is a 400, so the pack clamps instead of passing through.
  • Field names in raw stay Czech on purpose; the mapped fields are renamed to English so a caller does not need to know obchodniJmeno is the trading name.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "ares-cz": {
      "url": "https://gateway.pipeworx.io/ares-cz/mcp"
    }
  }
}
What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/ares-cz/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 1872+ 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/ares_lookup_ico \
  -H 'Content-Type: application/json' \
  -d '{"ico":"00177041"}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/ares_lookup_ico. 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": {
    "ares-cz": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-ares-cz"]
    }
  }
}

Or run it directly to confirm it starts:

npx -y @pipeworx/mcp-ares-cz

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 Ares Cz data" })

The gateway picks the right tool and fills the arguments automatically.

More

License

MIT

Frequently asked questions

What is Ares Cz?

Czech business register (ARES) — look up any Czech company or sole trader by IČO or by name, from…

How do I install Ares Cz?

It runs as a remote server. In Claude Code: claude mcp add --transport http ares-cz 'https://gateway.pipeworx.io/ares-cz/mcp'. For other clients, paste the JSON configuration from this page into their MCP settings.

Does Ares Cz need an API key?

Its registry entry lists no required key or secret. Some features may still need an account with the service it connects to.

Is Ares Cz open source?

Yes. Its code is on GitHub under the MIT license.

Who maintains Ares Cz?

It is published by pipeworx-io. AI.tn lists it but does not maintain or endorse it.

From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.