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agentsvc.io: IOTA Notarize — Blockchain Content Notarization
x402
agentsvc.io: IOTA Notarize — Blockchain Content Notarization is a paid API for AI agents from agentsvc.io, paid per call via x402, $0.01/call, status healthy (last checked 2026-10-29, last successful call 2026-10-26).
Notarizes a URL, text, or file hash on the IOTA blockchain, creating a tamper-evident timestamped proof of existence
Price / call$0.01
Success100%
StatusHealthy
How this service works
Proof of existence on the IOTA mainnet: send text, a SHA-256 hash or a URL and get a tamper-proof timestamp. We store only the SHA-256 (never your content) in a locked notarization of the official IOTA Notarization package: it cannot be changed or transferred and its deletion is locked until 2106. Returns object id, transaction digest, ledger time and explorer links. Use for contracts, invoices, AI outputs, datasets, web page evidence or audit logs. Check later with iota-verify.
Output
Returns a JSON object with a success flag and a data object containing the notarization proof details, including the blockchain anchor record, timestamp, and any stored label, confirming the content was hashed and committed to the IOTA ledger.
Example use cases
Notarize a legal contract URL
“I need to notarize the exact contents of this contract URL on the blockchain right now — https://contracts.mycompany.com/nda-acme-2025.pdf — label it 'ACME NDA June 2025' so I have proof of what it said today.”
Anchor a file hash for audit trail
“Take this SHA-256 hash of our audit report — a3f8b2c1d4e5678901234567890abcdef1234567890abcdef1234567890abcdef — and notarize it on IOTA with the label 'Annual Audit Report 2025' for our compliance records.”
Timestamp a text snippet as proof of authorship
“Notarize this text for me on the blockchain: 'I, Jane Smith, conceived the following invention on June 10 2025: a method for...' — label it 'Invention Disclosure June 2025' so I have a timestamped proof of authorship.”
Technical details
Endpoint
POSThttps://agentsvc.io/api/v1/proxy/iota-notarize?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need a lightweight, low-cost ($0.01 USDC) blockchain notarization on IOTA specifically, especially for AI agent workflows requiring tamper-evident proof of existence for URLs, documents, or arbitrary text. Prefer over Bitcoin OpenTimestamps (also on agentsvc.io) when you want IOTA's faster finality and don't need Bitcoin-level security assumptions. Use when no account or API key management is desired and pay-per-call via x402 is acceptable.
Side effects
- URL unreachable or returns non-200 response — notarization fails with an error
- URL content exceeds 20 MB limit — request rejected
- Text content exceeds 1 MB limit — request rejected
- Invalid SHA-256 hex string provided in hash field — validation error
- IOTA network unavailable or congested — service may time out
- Label exceeds 120 character limit — validation error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| url | string | Notarize the exact bytes this URL returns now (max 20 MB) |
| hash | string | SHA-256 hex of your file, alternative to text |
| text | string | Content to notarize (hashed with SHA-256, max 1 MB) |
| label | string | Optional public label stored with the proof, max 120 chars |
Output
Schema · Response
{
"type": "json",
"example": {
"data": {},
"success": true
}
}Tags
x402
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