Quick example calls — request → response

Three full request → response examples for the most common tools. All reproducible against the free anonymous tier — no signup, no API key. Calls are JSON-RPC over MCP Streamable HTTP at https://openregistry.sophymarine.com/mcp; for brevity we show the tool name + arguments + the unwrapped response.

1. search_companies — find a UK company

// Request
{
  "name": "search_companies",
  "arguments": { "jurisdiction": "GB", "query": "Monzo Bank", "limit": 5 }
}

// Response (truncated to 1 result)
{
  "jurisdiction": "GB",
  "count": 5,
  "results": [
    {
      "jurisdiction": "GB",
      "company_id": "09446231",
      "company_name": "MONZO BANK LIMITED",
      "status": "active",
      "incorporation_date": "2015-02-06",
      "registered_address": "Broadwalk House, 5 Appold Street, London, England, EC2A 2AG",
      "jurisdiction_data": {
        "company_number": "09446231",
        "company_status": "active",
        "company_type": "ltd",
        "date_of_creation": "2015-02-06",
        "title": "MONZO BANK LIMITED",
        "address_snippet": "Broadwalk House, 5 Appold Street, London...",
        "kind": "searchresults#company",
        "links": { "self": "/company/09446231" }
        // ... 20+ verbatim CH fields
      }
    }
  ]
}

2. get_persons_with_significant_control — UK PSC for a known company

// Request
{
  "name": "get_persons_with_significant_control",
  "arguments": { "jurisdiction": "GB", "company_id": "OC404063" }
}

// Response
[
  {
    "jurisdiction": "GB",
    "psc_id": "...",
    "name": "[REDACTED — UK CH residential-address suppression]",
    "kind": "individual-person-with-significant-control",
    "nature_of_control": ["ownership-of-shares-25-to-50-percent"],
    "notified_on": "2024-08-15",
    "is_active": true,
    "jurisdiction_data": {
      "etag": "...",
      "natures_of_control": ["ownership-of-shares-25-to-50-percent"],
      "notified_on": "2024-08-15",
      "country_of_residence": "United Kingdom",
      "date_of_birth": { "month": 7, "year": 1985 },
      "address": { "country": "United Kingdom" },
      "links": { "self": "/company/OC404063/persons-with-significant-control/individual/..." }
      // ... full CH PSC record
    }
  }
]

PSC ≠ shareholders. UK Companies House publishes a structured PSC register and a separate (filing-only) statement of capital. They disagree: a 10% shareholder appears in the statement of capital but not in PSC; a corporate trustee appears in PSC without being a shareholder. We surface both via get_persons_with_significant_control and get_shareholders respectively. See Iceland Foods chain walk.

3. fetch_document — raw iXBRL annual accounts bytes

// Request — get the document_id from list_filings or get_financials first
{
  "name": "fetch_document",
  "arguments": { "document_id": "MzQ0MTUyNDU5N2FkaXF6a2N4", "max_bytes": 5000000 }
}

// Response (metadata + base64-encoded body)
{
  "jurisdiction": "GB",
  "document_id": "MzQ0MTUyNDU5N2FkaXF6a2N4",
  "content_type": "application/xhtml+xml",
  "size_bytes": 348721,
  "encoding": "base64",
  "content": "PCFET0NUWVBFIGh0bWwgUFVCTElDIC...",
  // signed proxy URL for human download / out-of-band fetch
  "proxy_url": "https://openregistry.sophymarine.com/document/gb/MzQ0MTUyNDU5N2FkaXF6a2N4/content?token=..."
}

The content is the literal iXBRL bytes Companies House sends — your AI agent parses or re-renders as it sees fit. We don't re-encode, normalise tags, or extract figures into our own schema. Pass format: "png" (Browser Rendering required) to receive a rasterised page-by-page render of scanned PDFs instead.

Reproducing this

Connect any MCP client to https://openregistry.sophymarine.com/mcp, free anonymous tier (20 req/min/IP). Or browse the same data on the web at /company/gb/09446231 — the directors / PSC / filings / charges sub-pages are paid-tier on the web UI but the underlying data is free via MCP.