$0.01
per call · USD Coin on Base
Kairostamp evidence snapshot: server-side fetch of one public http/https URL, returning a time-stamped receipt with the response status, content type, byte length, SHA-256 of the body, redirect chain, a text preview, and a tamper-evident hash-chain entry.
Endpoint
POST https://kairostamp.com/api/v1/snapshot3
Calls / 30d
2
Unique payers / 30d
Aug 23
Last called
exact
Payment scheme
Call this service
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";
const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const fetchWithPay = wrapFetchWithPayment(fetch, account);
const res = await fetchWithPay("https://kairostamp.com/api/v1/snapshot", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({
"url": "https://example.com/"
}),
});
const data = await res.json();curl -X POST \
"https://kairostamp.com/api/v1/snapshot" \
-H "Content-Type: application/json" \
-d '{"url":"https://example.com/"}' \
-H "X-PAYMENT: <signed x402 payment>"Example response
{
"chain_hash": "d084fff3e5d852089814f7d4d3ffe9d04d1a39ce9d2e0573a95f24cf78fb584d",
"previous_chain_hash": "da27fe24efc04330962d1b95c7929a9de901ad0ea49a7997edf9f2731bf88def",
"receipt": {
"byte_length": 559,
"content_type": "text/html",
"fetched_at": "2026-08-21T06:32:12.771Z",
"redirect_chain": [],
"sha256": "ff67a9d764d6a2367a187734e697f6a53217db9a21c101d410a113ca871a299d",
"status_code": 200,
"text_preview": "<!doctype html><html lang=\"en\"><head><title>Example Domain</title>…",
"url": "https://example.com/"
},
"receipt_id": "85cd424c-b68b-440e-8f4f-e02147799f30"
}Payment details
0xdb6f694ae695c632c82677a50593b46137808453USD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913Is this your API?
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