UK Companies House due diligence and KYB (Registrum) MCP server

Registrum MCP Server

UK company data in your AI agent — without building Companies House plumbing.

No Companies House developer account, no rate-limit handling, no iXBRL parsing. Works in Claude Desktop, Claude Code, Cursor, and any MCP-compatible client.

<!-- Safe for production (docs-only). Keep the date true: RegistrumUK/uk-companies-house-mcp#42 --> Dependabot is enabled on all six Registrum repositories; as of 2026-10-08 there are zero open dependency alerts. See SECURITY.md.

Try it now — no signup, no key, no install

Point your client at the hosted endpoint and every tool answers with real data:

https://registrum.co.uk/api/mcp

{
  "mcpServers": {
    "registrum": {
      "url": "https://registrum.co.uk/api/mcp"
    }
  }
}

That is the whole setup. Ask it "Who ultimately owns BrewDog?" and it will trace the ownership chain to the named individuals who hold control.

One thing worth knowing before you test it on a household name: companies listed on a regulated market — Tesco, Rolls-Royce, most of the FTSE — are exempt from the PSC regime, so their ownership chain is legitimately empty and getpscchain says so rather than inventing a tree. Ownership questions are interesting on private companies, which is where the register actually records who is behind them.

The hosted endpoint has small daily caps, enough to see exactly what comes back. When you reach one, the tool tells you so and points at a free key; nothing silently degrades.

Three ways to use it

and ask about any UK company. No signup.

1. Try it - no key. Point your MCP client at https://registrum.co.uk/api/mcp

monthly cap, no card. After that the key stays free for light use.

1. Build with it - free key. 60 days of full access: every endpoint, no

Live prices and limits: GET /v1/plans.

1. Run on it - paid plan. When you need volume, premium endpoints or an SLA.

Why this instead of the Companies House API directly

Companies House publishes the raw register for free, and you can absolutely call it yourself. What you then own is the plumbing:

Other Companies House MCP servers make you bring your own CH key and hand back the raw response. This one does the enrichment.

Running it with your own key

Use a key to build on it (60 days of full access), or when you would rather run the server locally than call ours.

Claude Desktop — ~/.claude/claudedesktopconfig.json Cursor — .cursor/mcp.json (per project) or ~/.cursor/mcp.json (global)

Shortened. The full README is on GitHub.