companieswise
Verified UK company lookup & number validation for AI agents — official Companies House data, not guesses.
Verified, trustworthy data tools for AI agents. "Qiniso" means "truth" in Zulu.
Website · npm · MCP Registry
</div>Ask an LLM "what's the registered name and status of company 00445790?" and it will answer confidently — and usually wrongly: invented names, the wrong status, a fabricated incorporation date. Company records live in the Companies House register, not a model's weights. companieswise looks the number up in the official Companies House snapshot and returns the real registered details — or an honest "not found" instead of a guess.
⚠️ Read this first — what the data is
- UK-wide (England & Wales, Scotland, Northern Ireland).
- A monthly snapshot of the live register. Company status is as of the dataset date, not real-time — a company dissolved last week may still read "Active" until the next snapshot, and dissolved companies are generally absent. For current status, check the live register.
- Not advice. Not legal, financial, credit, or KYC/AML advice, and not a substitute for statutory due diligence.
Install
{ "mcpServers": { "companieswise": { "command": "npx", "args": ["-y", "companieswise"] } } }
Then load the real data once (the package ships with only a small sample):
npx -p companieswise companieswise-update
This downloads the latest monthly Companies House snapshot (~tens of MB) to a local cache. Re-run it whenever you want to refresh; a GitHub Action rebuilds the snapshot monthly, so companieswise-update always fetches the current month. Until you run it, validate_company_number works fully and lookup_company/search_company clearly say they're on the sample.
Optional: live mode (BYO key)
By default companieswise serves the monthly snapshot (offline, no key). If you set a free Companies House API key, it switches to live queries against the official Companies House API instead — real-time register status, including dissolved companies, on your own key (no shared rate limit):
{
"mcpServers": {
"companieswise": {
"command": "npx",
"args": ["-y", "companieswise"],
"env": { "COMPANIESWISE_CH_API_KEY": "your-companies-house-api-key" }
}
}
}
lookup_company and search_company use the live API when the key is set (results tagged "dataset": "live") and fall back to the snapshot when it isn't ("dataset": "snapshot"), so it's always clear which you're getting. validate_company_number is offline either way. The key is sent only to the official Companies House API. CH_API_KEY is accepted as an alias.
Use it as a library
npm i companieswise
import { lookupCompany, validateCompanyNumber, searchCompany } from "companieswise";
validateCompanyNumber("SC123456"); // { valid: true, prefix: "SC", meaning: "Company registered in Scotland" }
validateCompanyNumber("6").number; // "00000006" — normalises/zero-pads
lookupCompany("00000006"); // official name, status, type, incorporation date, postcode, SIC — or found:false
searchCompany("greggs"); // companies whose registered name contains your words
A well-formed number that isn't in the snapshot returns found: false with a clear note — it never invents a company.
Tools — 3
| Tool | What it answers |
|---|---|
| lookup_company | A company's official registered details by number (name, status, type, incorporation date, registered postcode, primary SIC) |
| validate_company_number | Is this a well-formed UK company number, and what does its prefix denote? (format only — there is no check digit) |
| search_company | Reverse lookup — find a company's number from its name |
Data & monthly auto-refresh
The data is the Companies House Free Company Data Product (UK-wide, live register), published under the Open Government Licence v3.0. Because the real dataset is ~5.6M companies — far too large to bundle into an npm package — the design splits code from data:
- Code ships on npm (tiny).
- Data is built monthly by a GitHub Action (
.github/workflows/refresh-data.yml) that downloads the official snapshot, compiles a compact artifact, and publishes it as a GitHub Release asset. companieswise-updatedownloads that artifact into a local cache; every response reports itsdatasetVersion(the snapshot date).
No API key, no rate limit, no per-request cost — lookups run locally against the cached snapshot. See ARCHITECTURE.md for why, and the hosted/real-time path.
What it is not
- Not real-time. Monthly snapshot of the live register; status is as of the dataset date. For live status use the Companies House API/website.
- Not the full register. The free snapshot is live companies; dissolved companies are generally absent (absent ≠ "never existed").
- Not advice, and not a statutory KYC/AML check.
- Not a guesser — unknown numbers return an honest "not found".
Privacy
This tool runs locally on your machine and is built not to collect, store, or transmit your data — no analytics, no telemetry, no account. By default it uses bundled/cached data offline; only if you set a Companies House API key does it send your lookup and key directly to the official Companies House API (never to Qiniso). Full policy: https://qinisolabs.github.io/privacy.html.
License
Apache-2.0. Company data © Crown copyright, Companies House, Open Government Licence v3.0; see NOTICE.