# AgentShelf DNS A Record Lookup

> AgentShelf DNS A Record Lookup is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.006/call, status unknown (last checked 2026-10-01).

Resolves a hostname to its IPv4 addresses only, returning an error if no A records are found.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/dns-a?utm_source=zero.xyz
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-dns-a-record-lookup-7020f767
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OMRSCZkfwjt6Zqv-5NtMr

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 agentshelf-dns-a-record-lookup-7020f767 -d '<json body>'
```

Example prompt: What IPv4 addresses does api.example.com resolve to? I need only the A records — if there are none, treat it as an error.

## When to prefer this

Choose this endpoint when you specifically need IPv4 (A record) DNS resolution and require that an empty result be treated as a hard error. Prefer the free POST /v1/sandbox/dns-a first for testing. Use this over a bundled DNS-lookup SKU when you want strict IPv4-only results without silent empty responses.

## Known failure modes

- Hostname has no A records — returns an error (empty result is not allowed)
- Invalid or malformed hostname — validation error
- Hostname does not exist (NXDOMAIN) — error response
- Private or internal hostnames may not resolve publicly
- Network timeout from DNS resolver — error response

## How this service works

Call when an agent needs IPv4 addresses only. Empty is an error, unlike the bundled dns-lookup SKU. Exact $0.006 USDC. Prefer unpaid POST /v1/sandbox/dns-a first.

## Output

Returns the resolved IPv4 addresses (A records) for the given hostname. If the hostname has no A records, an error is returned rather than an empty result — this distinguishes it from a bundled DNS lookup that tolerates empty responses.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "hostname": {
   "type": "string",
   "examples": [
    "example.com"
   ],
   "maxLength": 253,
   "minLength": 1,
   "description": "Public DNS hostname such as example.com. Not a URL, not an IP literal, and not a private name."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-dns-a-record-lookup-7020f767/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)