# AgentShelf URL Protocol Checker

> AgentShelf URL Protocol Checker is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.007/call, status unknown (last checked 2026-10-11).

Determines whether a given URL uses HTTP or HTTPS protocol without fetching the URL's content

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/check-url-web?utm_source=zero.xyz
- Price: $0.007/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-url-protocol-checker-8906ba76
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_me2c5Wf3mSXJYUrMEzrxF

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-url-protocol-checker-8906ba76 -d '<json body>'
```

Example prompt: Can you check whether this URL uses HTTP or HTTPS: 'http://example.com/page'?

## When to prefer this

Use this endpoint when you need a quick, no-fetch protocol check on a URL string and are willing to pay $0.007 USDC per call. Prefer the free sandbox alternative (POST /v1/sandbox/check-url-web) when available. Choose this over full HTTP fetch endpoints when you only need the protocol (http vs https) and do not need the page content.

## Known failure modes

- Empty or missing URL value returns a validation error
- URL string exceeds 20,000 character limit
- Malformed or non-URL string may return an error or unexpected result
- Service unavailable or payment failure (402) if USDC payment is not attached

## How this service works

Call when an agent needs whether a URL is http or https. No fetch. Send JSON {"value":"https://example.com/a"}. Exact $0.007 USDC on Base. Try unpaid POST /v1/sandbox/check-url-web first.

## Output

Returns an indication of whether the given URL uses the HTTP or HTTPS protocol, derived purely from parsing the URL string without making any network request to the target.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "description": "JSON value for schema-check SKUs. Omit it on string checks such as email or IBAN."
  },
  "value": {
   "type": "string",
   "examples": [
    "https://example.com/a"
   ],
   "maxLength": 20000,
   "minLength": 1,
   "description": "Value to check. The route description names the format: email, phone, IBAN, postal code, VAT, national id, or similar."
  },
  "schema": {
   "description": "JSON Schema document for schema-check SKUs. Omit it on string checks."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-url-protocol-checker-8906ba76/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)