Bitcoin Timestamp (OpenTimestamps)

Timestamp anything on Bitcoin with OpenTimestamps: send text, a SHA-256 hash or a URL and get a standard .ots proof (base64). Only a salted hash leaves our server. The public calendars anchor it in a Bitcoin block within hours; then btc-timestamp-verify returns the block and the complete proof, which anyone can check with the open-source ots tool. For contracts, AI outputs, datasets, invoices and web evidence.

Run free trial ↗3 free calls per day with the example input. Paid: $0.005 USDC, no limit.

Call it

import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agentsvc.io/api/v1/proxy/btc-timestamp", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({"text":"Contract draft v3, agreed 2026-10-11"}),
});
const { data, payment } = await res.json();  // payment.status "settling"; header X-Payment-Settle: sync returns payment.transaction

Input

Field	Type	Description
text	string	Content to timestamp (hashed with SHA-256)
hash	string	SHA-256 hex, alternative to text
url	string	Timestamp the exact bytes this URL returns now

Output

Field	Type	Description
sha256	string
status	string
ots_base64	string
calendars	array
next_step	string