# AgentShelf Link Status Checker

> AgentShelf Link Status Checker is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-01).

Performs HTTP HEAD requests on up to 20 public URLs and returns status codes, SSRF-safe, for $0.01 USDC per call.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/link-status?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-link-status-checker-63d0b784
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-HrE_8d1_BlmVYhhR8zKB

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-link-status-checker-63d0b784 -d '<json body>'
```

Example prompt: Can you check whether these 5 URLs are actually reachable right now: https://example.com, https://docs.acme.io/guide, https://blog.company.com/post-1, https://cdn.assets.io/logo.png, and https://api.partner.dev/health?

## When to prefer this

Use this endpoint when you need bulk HEAD-only status checks across up to 20 public URLs in a single paid call and want SSRF safety guarantees. Prefer the free POST /v1/sandbox/link-status endpoint for testing or low-volume checks first. Choose this over full-page scraping endpoints when you only need HTTP status (not page content), saving bandwidth and cost. Best for link validation, uptime probing, and pre-publish link audits.

## Known failure modes

- URL targets private or metadata IP ranges (SSRF protection rejects request)
- URL string exceeds 2048 characters
- Array contains more than 20 URLs (validation error)
- Array is empty (minItems:1 violated)
- Target URL is unreachable or times out (may return error status per URL)
- Malformed URL format rejected at input validation

## How this service works

Call when an agent needs HEAD status for up to 20 public URLs (SSRF-safe). Exact $0.01 USDC. Prefer unpaid POST /v1/sandbox/link-status first.

## Output

Returns HTTP HEAD response status codes (e.g. 200, 301, 404, 500) for each submitted URL, allowing the agent to determine link reachability and health without downloading full page content. Results are SSRF-safe, meaning private/metadata IP ranges are blocked.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "urls": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 2048,
    "minLength": 8
   },
   "examples": [
    [
     "https://example.com/",
     "https://example.com/widget"
    ]
   ],
   "maxItems": 20,
   "minItems": 1,
   "description": "One to 20 public http(s) URLs. Each is checked with HEAD and a GET fallback."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-link-status-checker-63d0b784/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)