# SiteCheck Identifier Validator

> SiteCheck Identifier Validator is a paid API for AI agents from api.sitecheck-api.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-14).

Validates one or more identifiers (ISBN, EAN, VIN, IMEI, ISIN, LUHN, or auto-detected) and returns whether they are valid along with normalized form and parsed parts

## Facts

- Endpoint: GET https://api.sitecheck-api.workers.dev/api/validate?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sitecheck-identifier-validator-f36a3a40
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_BXlrtu_R_xmhAP_vgpphE

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 sitecheck-identifier-validator-f36a3a40
```

Example prompt: Can you check if the ISBN '0306406152' is valid and show me its ISBN-13 equivalent?

## When to prefer this

Use this endpoint when you need fast, cheap ($0.001 per call), pay-per-use validation of structured identifiers like ISBNs, VINs, IMEIs, EANs, ISINs, or Luhn-checksum values without requiring any signup. It supports auto-detection of identifier type and batch validation of up to 50 identifiers per call. Prefer this over building custom check-digit logic or using heavier data enrichment services when all you need is a validity check and normalized form.

## Known failure modes

- Invalid or unrecognizable identifier format returns valid: false with the detected type
- Supplying more than 50 comma-separated values may be rejected or silently truncated
- Unknown identifier type when type is set to 'auto' and the value doesn't match any known pattern
- Missing required 'value' query parameter returns an error response
- Malformed query string or non-string value types may cause a 400-level error

## How this service works

Pay-per-call tools for AI agents: image generation, speech-to-text, text-to-speech, embeddings, LLM chat, website audits and contact enrichment, web page to Markdown reader, PDF to text, sitemap URLs, tech stack detection, translation, exchange rates, e-mail pre-check, domain RDAP/DNS lookup, Solana token checks, trending tokens and wallet holdings, plus business and compliance data (EU VAT/VIES, IBAN, LEI/GLEIF, US recalls, OSHA/EPA violations, UK insolvency notices). Also: SEO metadata, link checking, redirect chains, security headers, mail DNS (SPF, DMARC, DKIM), QR codes, language detection, photo EXIF, identifier validation, image OCR, SEC filings, SEC financials, Congress bills, macro rates, UK company data, GitHub repo stats, Hacker News, Wikipedia, gas prices, Solana swap quotes, ERC-20 token checks, ENS names, EVM wallet balances, EVM balances, transactions and contract calls, Solana transactions and accounts, crypto prices, candles and order books, DeFi TVL, yields and stablecoins, SEC insider trades, weather, geocoding and holidays, IP owners and postcodes, npm, PyPI and crates package data and vulnerabilities, GitHub profiles, arXiv papers and DOIs, structured extraction, summaries, sentiment and reranking, HTML tables and RSS feeds, Bitcoin fees, addresses and transactions, Bitcoin address balances, Bitcoin transaction status, EVM calldata decoding, verified EVM contracts, Hyperliquid perpetual markets, Hyperliquid account positions, Polymarket odds, crypto fear and greed, DeFi fees, DEX volume, company registries of four countries, ISIN, CUSIP and ticker lookup, SEC full-text search, SEC 8-K events, FDA drug labels, FDA adverse event counts, clinical trials, PubMed articles, US federal grants, EU public tenders, NPI provider lookup, US address geocoding, USGS earthquakes, NWS weather alerts, sunrise and moon times, time zone conversion, distance and bearing, GDACS disaster alerts, llms.txt checks, AI crawler access, tracker and cookie audits, certificate transparency, site logos and icons, GitHub releases, GitHub issues, Stack Overflow answers, read-only Wikidata queries, text moderation, image descriptions, text classification, named entity extraction, PII redaction, phone number checks, cron explanations, JSON Schema validation. Plus prediction-market search, briefs, quotes and unsigned buy transactions, powered by Panta. Payment: x402, USDC on Base, Solana or Arc. No signup, no API key.

## Output

A JSON object containing the identifier value, detected or specified type (isbn, ean, vin, imei, isin, luhn), a valid boolean, normalized form, any parsed sub-parts (e.g. isbn13), the expected check digit if applicable, and a checkedAt timestamp. Up to 50 identifiers can be validated in a single call.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "value"
     ],
     "properties": {
      "type": {
       "type": "string",
       "description": "auto (default), isbn, ean, vin, imei, isin or luhn"
      },
      "value": {
       "type": "string",
       "description": "The identifier, or up to 50 comma-separated"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "type": "isbn",
  "parts": {
   "isbn13": "9780306406157"
  },
  "valid": true,
  "value": "0306406152",
  "subtype": "ISBN-10",
  "checkedAt": "2026-10-13T09:00:00.000Z",
  "normalised": "0306406152",
  "expectedCheckDigit": null
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sitecheck-identifier-validator-f36a3a40/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.sitecheck-api.workers.dev](https://www.zero.xyz/host/api.sitecheck-api.workers.dev/llms.txt)