Grok UK Companies House (Registrum) - no API key get_financials
How to: Grok UK Companies House (Registrum) - no API key get_financials
Add UK Companies House (Registrum) - no API key to Grok
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01
Open .mcp.json (in your project root) and merge this in. Keep any servers already there.
{
"mcpServers": {
"uk-companies-house-mcp": {
"type": "http",
"url": "https://registrum.co.uk/api/mcp"
}
}
}-
02
Save the file and restart Grok.
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03
Ask for something get_financials does. Grok lists the server's tools on connect and calls get_financials itself — you do not invoke it by name.
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04
If nothing happens, check the server is running and that UK Companies House (Registrum) - no API key's identifier in your config matches the one above exactly.
Grok Build reads Claude Code's .mcp.json and Claude Desktop's config unchanged, so a server you have already set up there needs nothing new. The Grok web app and X integration do not take custom servers. Grok docs
Set these first
UK Companies House (Registrum) - no API key will not start until these are set, so get_financials never becomes available.
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REGISTRUM_API_KEY
Same tool, other clients
This list was read from the server itself, by connecting to it and calling tools/list on 8 October 2026. It is what
the server actually exposes, not what its listing claims.
Mutating and Read-only are read off each tool's name, not its schema — a hint, not a guarantee. The registry stores tool names only; connect the server for its live schemas.