# Arch Tools Domain Check

> Arch Tools Domain Check is a paid API for AI agents from archtools.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Checks the availability and registration status of a domain name

## Facts

- Endpoint: POST https://archtools.dev/v1/tools/domain-check
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/arch-tools-domain-check-83345a8e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CO9lkyBTB94JhI2qc0GvZ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability arch-tools-domain-check-83345a8e -d '<json body>'
```

Example prompt: Can you check if coolstartup.io is available to register?

## When to prefer this

Use this endpoint when you need a quick, pay-per-call domain availability or registration status check without setting up a full domain registrar API integration. Particularly useful for agents doing ad-hoc domain research, brand name validation, or pre-purchase checks on individual domains.

## Known failure modes

- Invalid or malformed domain string returns an error response
- Domain TLD not supported may return an error or empty result
- Network timeout or upstream DNS/WHOIS service unavailability
- Rate limiting if too many requests are made in quick succession

## How this service works

Check if a domain is available or registered via RDAP (no key needed). Pay per call with USDC (x402) or credits - archtools.dev

## Output

A JSON object indicating whether the given domain is available or already registered, along with relevant domain metadata such as registration status and potentially registrant or expiry details.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "domain": {
   "type": "string",
   "description": "Domain name (e.g. example.com)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/arch-tools-domain-check-83345a8e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from archtools.dev](https://www.zero.xyz/host/archtools.dev/llms.txt)