Companies House MCP Server

A local MCP server that exposes the UK Companies House API as tools for Claude Desktop and Cowork.

Tools

• search_companies — Search by name or number

• get_company_profile — Full profile (status, address, SIC codes, accounts dates)

• get_officers — Directors and secretaries (current and resigned)

• get_pscs — Persons with significant control (shareholders >25%)

• get_filing_history — Filed documents (filterable by category)

• get_document_info — Document metadata (formats, page count)

• download_ixbrl — Download accounts as machine-readable iXBRL

• get_charges — Registered charges/mortgages

Related MCP server: my-first-mcp

Setup

1. Get an API key

Register for free at https://developer.company-information.service.gov.uk

2. Install

cd companies-house-mcp
pip install -e .

Or with uv:

cd companies-house-mcp
uv pip install -e .

3. Add to Claude Desktop

Open Claude Desktop settings and add to your MCP servers config (~/.claude/claude_desktop_config.json):

{
  "mcpServers": {
    "companies-house": {
      "command": "python",
      "args": ["/full/path/to/companies-house-mcp/server.py"],
      "env": {
        "COMPANIES_HOUSE_API_KEY": "your-api-key-here"
      }
    }
  }
}

Or if using uv:

{
  "mcpServers": {
    "companies-house": {
      "command": "uv",
      "args": ["run", "--directory", "/full/path/to/companies-house-mcp", "python", "server.py"],
      "env": {
        "COMPANIES_HOUSE_API_KEY": "your-api-key-here"
      }
    }
  }
}

4. Restart Claude Desktop

The Companies House tools will appear in your next session.

Testing

Run the server directly to check it starts:

COMPANIES_HOUSE_API_KEY=your-key python server.py