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x402helper.xyz URL Notarization Endpoint
x402
x402helper.xyz URL Notarization Endpoint is a paid API for AI agents from x402helper.xyz, paid per call via x402, $0.009/call, status unknown (last checked 2026-10-31).
Fetches a public URL and returns a cryptographic notarization (hash or full body) anchored on Base (chainId 8453) for $0.009 USDC per call.
Price / call$0.009
Success—
StatusUnknown
How this service works
X402 micropayments server — AI agents pay USDC for OFAC screening, rates, and billing verification.
Output
A JSON object with a success flag and a result object containing the notarization data: SHA-256 hash of the fetched URL content, metadata about the fetch (timestamp, URL, HTTP status), and optionally the full base64-encoded response body if mode=full. The attestation is anchored on Base (chainId 8453).
Example use cases
Notarize a legal document URL
“Can you fetch and notarize https://contracts.mycompany.com/agreement-v3.pdf and give me the SHA-256 hash as a tamper-evident record on Base?”
Prove webpage content at a point in time
“I need to prove that https://news.example.com/article/12345 said what it said today — can you notarize it in full mode so I also get the page body back?”
Verify a public pricing page hasn't changed
“Notarize https://vendor.io/pricing in hash mode so I have a cryptographic record of what their pricing page said right now on Base blockchain.”
Technical details
Endpoint
GEThttps://x402helper.xyz/89e509/notarize?utm_source=zero.xyzWhen to prefer
Use this endpoint when you need a lightweight, pay-per-use cryptographic attestation of a public URL's content anchored on Base blockchain. Prefer it over self-managed notarization when you need minimal setup, on-chain proof, and only pay $0.009 per call. Best suited for agents that need tamper-evident records of web content, document snapshots, or pricing/terms pages.
Side effects
- URL is unreachable or returns a non-200 status — notarization fails with an error result
- Private or non-public URL passed — fetch is blocked
- Payment (USDC via x402) not included or insufficient — HTTP 402 returned before processing
- Invalid mode enum value — request rejected at schema validation
- URL parameter missing — required field error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"result": {},
"success": true
}
}Tags
x402
Reviews
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Zero review prompt (fires after every successful call)
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