---
title: "Documentation"
url: "https://lookvalid.com/docs.md"
canonical_url: "https://lookvalid.com/docs"
last_updated: "2026-10-22"
type: "index"
summary: "Guides and reference for the LookValid API: quickstart, authentication, credits, rate limits, errors and MCP."
---

# Documentation

Guides and reference for the LookValid API: quickstart, authentication, credits, rate limits, errors and MCP.

LookValid is one API key and one credit balance for many lookup products: phone numbers, email domains, IP addresses, domains and websites. You call a product, get a JSON answer, and spend credits only when the lookup finds something.

## How it works

- **One key.** The same API key works for every product, for the account endpoints and for the MCP server.
- **One balance.** Every product spends from a single credit balance. There is no per-product wallet to top up.
- **Pay for answers.** Most products use success billing: a lookup that finds nothing is free. See [credits and billing](https://lookvalid.com/docs/credits-and-billing.md).
- **Repeats are free.** Results are cached per account for 7 days, and repeating a lookup in that window costs nothing.
- **Built for agents.** Every product is an MCP tool, and every docs page is available as markdown. Add `.md` to any docs URL.

## Products

Every product below takes the same API key and spends from the same credit balance.

| Product | Credits | Billing | What one unit is | Reference |
| --- | --- | --- | --- | --- |
| Phone Numbering-Plan Validation | 1 | Success only | per valid number | [`POST /v1/phone`](https://lookvalid.com/docs/api/phone.md) |
| Country Calling Codes | 1 | Success only | per lookup (an unknown code, country or name is free) | [`POST /v1/country-code`](https://lookvalid.com/docs/api/country-code.md) |
| Email Domain Check | 1 | Success only | per address checked | [`POST /v1/email-domain-check`](https://lookvalid.com/docs/api/email-domain-check.md) |
| IP Intelligence | 1 | Success only | per lookup | [`POST /v1/ip`](https://lookvalid.com/docs/api/ip.md) |
| Phone Spam Check | 1 | Success only | per number with complaints on record | [`POST /v1/phone-spam`](https://lookvalid.com/docs/api/phone-spam.md) |
| Link Safety Check | 1 | Every call | per URL checked (a check that cannot run is free) | [`POST /v1/link-safety`](https://lookvalid.com/docs/api/link-safety.md) |
| Carrier Lookup (original carrier) | 1 | Success only | per lookup (numbers outside the covered numbering plan areas are free) | [`POST /v1/carrier-lookup`](https://lookvalid.com/docs/api/carrier-lookup.md) |
| VIN Decoder | 1 | Success only | per VIN that decodes (a VIN with no data is free) | [`POST /v1/vin-decoder`](https://lookvalid.com/docs/api/vin-decoder.md) |
| Link-in-Bio Lookup | 3 | Success only | per resolved page (dead or empty pages are free) | [`POST /v1/link-in-bio-lookup`](https://lookvalid.com/docs/api/link-in-bio-lookup.md) |
| Domain Authority | 10 | Success only | per domain found in the rank data (an unranked domain is free) | [`POST /v1/domain-authority`](https://lookvalid.com/docs/api/domain-authority.md) |
| Domain Age | 2 | Success only | per registered domain (unregistered domains are free) | [`POST /v1/domain-age`](https://lookvalid.com/docs/api/domain-age.md) |
| Website Scraper | 10 | Success only | per successful scrape (errors, empty and blocked pages are free) | [`POST /v1/website-scraper`](https://lookvalid.com/docs/api/website-scraper.md) |
| Website Contacts Scraper | 10 | Success only | per domain with contacts found | [`POST /v1/website-contacts-scraper`](https://lookvalid.com/docs/api/website-contacts-scraper.md) |
| Site Files Checker | 2 | Success only | per site checked (a site that cannot be reached is free) | [`POST /v1/site-files`](https://lookvalid.com/docs/api/site-files.md) |

## Where to start

- [Quickstart](https://lookvalid.com/docs/quickstart.md): get a key and make your first request in cURL, Node.js or Python.
- [Authentication](https://lookvalid.com/docs/authentication.md): how to send your key and keep it safe.
- [Credits and billing](https://lookvalid.com/docs/credits-and-billing.md): what a lookup costs and when you are charged.
- [Rate limits](https://lookvalid.com/docs/rate-limits.md): the limits per key and the headers that report them.
- [Errors](https://lookvalid.com/docs/errors.md): every error code and how to fix it.
- [MCP server](https://lookvalid.com/docs/mcp.md): use every lookup from Claude, Cursor or Codex.
- [API reference](https://lookvalid.com/docs/api.md): one page per endpoint, generated from the OpenAPI document.

## Base URL

```text
https://YOUR_API_HOST
```

`YOUR_API_HOST` stands for the API address that comes with your key; every example in these docs uses it. The [API reference](https://lookvalid.com/docs/api.md) describes every endpoint. For AI agents there is [llms.txt](https://lookvalid.com/llms.txt).