# XUB Domain Boundary Parser

> XUB Domain Boundary Parser is a paid API for AI agents from xub.me, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-22).

Parses hostnames to extract domain components including public suffix, registrable domain, subdomain, and IP/ICANN/private classification.

## Facts

- Endpoint: POST https://xub.me/api/tools/domain-boundary/invoke?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/xub-domain-boundary-parser-9e181761
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XFFfJ-V2MTJlpVCXwTcfo

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 xub-domain-boundary-parser-9e181761 -d '<json body>'
```

Example prompt: Parse the hostname 'blog.example.co.uk' and tell me its registrable domain, public suffix, subdomain, and whether it's an ICANN-recognized or private domain.

## When to prefer this

Choose this endpoint when you need reliable, standards-based domain decomposition using the Mozilla Public Suffix List — especially when you need to distinguish ICANN-recognized TLDs from private registries (e.g. github.io, pages.dev). Prefer this over simple string splitting or regex-based approaches that cannot handle multi-part suffixes like co.uk or com.au correctly.

## Known failure modes

- Invalid or malformed hostname input may return empty or null component fields
- IP addresses are flagged via isIp but may have limited decomposition
- Private suffix classification depends on the bundled tldts version and may lag behind latest Public Suffix List updates
- Non-existent TLDs may be parsed but flagged as non-ICANN

## How this service works

Machine-first x402 procurement intelligence and paid utilities.

## Output

Returns a JSON array of parsed domain objects for each input hostname, each containing: the original input, hostname, registrable domain, domain without suffix, subdomain, public suffix, and boolean flags for isIp, isIcann, and isPrivate. Also includes the tldts library version used and whether private domains were included in lookup.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tool": "domain-boundary",
  "result": {
   "results": [
    {
     "isIp": false,
     "input": "a.example.co.uk",
     "isIcann": true,
     "hostname": "a.example.co.uk",
     "isPrivate": false,
     "subdomain": "a",
     "publicSuffix": "co.uk",
     "registrableDomain": "example.co.uk",
     "domainWithoutSuffix": "example"
    },
    {
     "isIp": false,
     "input": "project.github.io",
     "isIcann": false,
     "hostname": "project.github.io",
     "isPrivate": true,
     "subdomain": "",
     "publicSuffix": "github.io",
     "registrableDomain": "project.github.io",
     "domainWithoutSuffix": "project"
    }
   ],
   "dataVersion": "tldts-7.4.18",
   "includePrivateDomains": true
  },
  "version": "1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/xub-domain-boundary-parser-9e181761/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from xub.me](https://www.zero.xyz/host/xub.me/llms.txt)