# Check Domain Availability

> Check Domain Availability is a paid API for AI agents from domains.rapidruntime.com, paid per call via MPP, price unknown, status unknown (last checked 2026-09-14).

Checks availability and pricing for up to 50 specific domain names before registration

## Facts

- Endpoint: POST https://domains.rapidruntime.com/api/v1/domains/check-availability
- Price: price unknown
- Payment: MPP
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Provider: domains.rapidruntime.com
- Website: https://domains.rapidruntime.com
- Canonical page: https://www.zero.xyz/c/domains-rapidruntime-com-check-domain-availability-fd624ea5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WckNLNSLV6eq1LIrkBCR8

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 domains-rapidruntime-com-check-domain-availability-fd624ea5 -d '<json body>'
```

Example prompt: Can you check if 'rapidlaunch.io', 'rapidlaunch.com', and 'rapidlaunch.co' are available to register and what they each cost?

## When to prefer this

Use this endpoint when you already know the exact domain names you want to check, especially before calling the registration endpoint to confirm current pricing. For exploratory keyword-based searching across many TLDs, prefer the keyword domain search endpoint instead.

## Known failure modes

- Empty or missing domainNames array returns validation error
- More than 50 domains in the request returns a 400 error
- Malformed domain names may return unavailable or error status
- Network timeout if the upstream registry is slow to respond
- Unknown TLDs may return an unsupported or unavailable result

## How this service works

Check availability and pricing for specific domain names. Use this before registration to confirm the exact price.

## Output

Returns an array of results for each queried domain name, including the domain name, SLD, TLD, whether it is purchasable, the purchase price, renewal price, whether it is a premium domain, and the reason if unavailable.

## Example request

```json
{
 "domainNames": [
  "testexample.com",
  "testexample.io",
  "testexample.co"
 ]
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "domainNames"
 ],
 "properties": {
  "domainNames": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "maxItems": 50,
   "minItems": 1,
   "description": "Domain names to check (max 50)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "results"
 ],
 "properties": {
  "results": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "domainName"
    ],
    "properties": {
     "sld": {
      "type": "string"
     },
     "tld": {
      "type": "string"
     },
     "reason": {
      "type": "string"
     },
     "premium": {
      "type": "boolean"
     },
     "domainName": {
      "type": "string"
     },
     "purchasable": {
      "type": "boolean"
     },
     "purchaseType": {
      "type": "string"
     },
     "renewalPrice": {
      "type": "number"
     },
     "purchasePrice": {
      "type": "number"
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/domains-rapidruntime-com-check-domain-availability-fd624ea5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from domains.rapidruntime.com](https://www.zero.xyz/host/domains.rapidruntime.com/llms.txt)