# AgentShelf DNS TXT ADSP Lookup

> AgentShelf DNS TXT ADSP Lookup is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.007/call, status unknown (last checked 2026-10-01).

Retrieves the DNS TXT record at _adsp._domainkey for a given hostname to check Author Domain Signing Practices (ADSP) policy.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/dns-txt-adsp?utm_source=zero.xyz
- Price: $0.007/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-txt-adsp-lookup-558af7e3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vfCNzINP1a5gWmYBr3vMr

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-txt-adsp-lookup-558af7e3 -d '<json body>'
```

Example prompt: What's the _adsp._domainkey DNS TXT record for example.com? I need to check its Author Domain Signing Practices policy.

## When to prefer this

Use this endpoint when you specifically need to retrieve the ADSP (_adsp._domainkey) DNS TXT record for a domain as part of email authentication auditing, DKIM compliance checking, or domain security analysis. Prefer this over general DNS lookup tools when you need a focused, paid, reliable lookup of this specific record type without setting up DNS resolution infrastructure yourself.

## Known failure modes

- No ADSP record exists at _adsp._domainkey for the given hostname — returns empty or not-found response
- Invalid or malformed hostname input — returns validation error
- DNS resolution timeout or upstream DNS failure — returns error
- Hostname exceeds 253 character limit — schema validation error
- Payment not provided or insufficient — returns 402 Payment Required

## How this service works

Call when an agent needs TXT at _adsp._domainkey. Exact $0.007 USDC. Prefer unpaid POST /v1/sandbox/dns-txt-adsp first.

## Output

Returns the content of the DNS TXT record published at _adsp._domainkey.<hostname>, representing the domain's Author Domain Signing Practices (ADSP) policy, such as 'dkim=all', 'dkim=discardable', or 'dkim=unknown', or an indication that no record exists.

## 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-txt-adsp-lookup-558af7e3/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)