HTML Clean Text API

POST /v1/html-clean-text
content-type: application/json
payment-signature: <base64 x402 payload>

{
  "url": "https://grist.tools/samples/web/render-article.html",
  "include_links": true,
  "readability": true,
  "max_chars": 2000
}

200 OK
payment-response: <base64 settlement receipt>

{
  "requested_url": "https://grist.tools/samples/web/render-article.html",
  "source_url": "https://grist.tools/samples/web/render-article.html",
  "final_url": "https://grist.tools/samples/web/render-article.html",
  "content_type": "text/html",
  "charset": "utf-8",
  "http_status": 200,
  "title": "Measuring Rainfall with a Simple Gauge",
  "byline": "Sample Author",
  "excerpt": "A short guide to reading a cylinder rain gauge at the same hour every day.",
  "site_name": "Grist Samples",
  "lang": "en",
  "lang_source": "html_lang",
  "text": "A cylinder rain gauge is a clear tube with a scale printed on the side. Rain falls through a funnel at the top and collects in the tube, where the water level shows how much fell since the last reading.\nThe most useful habit is consistency. Read the gauge at the same hour every day, ideally in the morning, so that each number covers one full day.\nPlacing the gauge\nPut the gauge in an open spot, away from walls, trees and roofs. A good rule is to keep it at least twice as far from any obstacle as the obstacle is tall.\nMount it level, so the scale reads true.\nKeep the funnel clear of leaves and insects.\nEmpty the tube right after each reading.\nReading the scale\nBend down until your eye is level with the water. The surface curves slightly where it meets the tube; read the number at the bottom of that curve.\nWrite the reading in a notebook with the date and time. A printable schedule helps when several people share the job.",
  "markdown": "A cylinder rain gauge is a clear tube with a scale printed on the side. Rain falls through a funnel at the top and collects in the tube, where the water level shows how much fell since the last reading.\n\nThe most useful habit is consistency. Read the gauge at the same hour every day, ideally in the morning, so that each number covers one full day.\n\n## Placing the gauge\n\nPut the gauge in an open spot, away from walls, trees and roofs. A good rule is to keep it at least twice as far from any obstacle as the obstacle is tall.\n\n-   Mount it level, so the scale reads true.\n-   Keep the funnel clear of leaves and insects.\n-   Empty the tube right after each reading.\n\n## Reading the scale\n\nBend down until your eye is level with the water. The surface curves slightly where it meets the tube; read the number at the bottom of that curve.\n\nWrite the reading in a notebook with the date and time. A [printable schedule](https://grist.tools/samples/web/render-print.html) helps when several people share the job.",
  "word_count": 178,
  "char_count": 933,
  "truncated": false,
  "readability_applied": true,
  "links": [
    {
      "href": "https://grist.tools/samples/web/render-print.html",
      "text": "printable schedule",
      "rel": null,
      "is_internal": true
    }
  ],
  "link_count": 1,
  "fetched_at": "2026-09-01T12:00:00.000Z"
}

// html-clean-text: $0.002 per call, paid in USD Coin on eip155:8453 via x402
// Install: npm install @x402/fetch@2 @x402/evm@2 viem@2
// Save as client.mjs (ES module, Node 18+), export EVM_PRIVATE_KEY with the paying wallet's key in your shell, then run: node client.mjs
// The wrapper reads the 402 (payment-required), signs and retries with payment-signature.
import { wrapFetchWithPayment, x402Client, decodePaymentResponseHeader } from '@x402/fetch'
import { ExactEvmScheme } from '@x402/evm/exact/client'
import { privateKeyToAccount } from 'viem/accounts'

const account = privateKeyToAccount(process.env.EVM_PRIVATE_KEY)
const client = new x402Client().register('eip155:8453', new ExactEvmScheme(account))
const fetchWithPayment = wrapFetchWithPayment(fetch, client)

const body = {
  "url": "https://grist.tools/samples/web/render-article.html",
  "include_links": true,
  "readability": true,
  "max_chars": 2000
}

const res = await fetchWithPayment('https://grist.tools/v1/html-clean-text', {
  method: 'POST',
  headers: { 'content-type': 'application/json' },
  body: JSON.stringify(body),
})
console.log(res.status, await res.json())
const settle = res.headers.get('payment-response')
if (settle) console.log(decodePaymentResponseHeader(settle).transaction)

# html-clean-text: $0.002 per call, paid in USD Coin on eip155:8453 via x402
# Install: pip install "x402[requests,evm]>=2.24,<3"
# The session reads the 402 (payment-required), signs and retries with payment-signature.
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http import decode_payment_response_header
from x402.http.clients.requests import x402_requests
from x402.mechanisms.evm.exact import register_exact_evm_client
from x402.mechanisms.evm.signers import EthAccountSigner

account = Account.from_key(os.environ["EVM_PRIVATE_KEY"])
client = x402ClientSync()
register_exact_evm_client(client, EthAccountSigner(account), networks="eip155:8453")
session = x402_requests(client)

payload = {
    "url": "https://grist.tools/samples/web/render-article.html",
    "include_links": True,
    "readability": True,
    "max_chars": 2000
}

res = session.post("https://grist.tools/v1/html-clean-text", json=payload)
print(res.status_code, res.json())
settle = res.headers.get("payment-response")
if settle:
    print(decode_payment_response_header(settle).transaction)

# html-clean-text: $0.002 per call, paid in USD Coin on eip155:8453 via x402
# 1. Unpaid call: HTTP 402, the requirements in the payment-required header (base64 JSON) and in the body.
curl -i -X POST 'https://grist.tools/v1/html-clean-text' -H 'content-type: application/json' -d '{"url":"https://grist.tools/samples/web/render-article.html","include_links":true,"readability":true,"max_chars":2000}'

# 2. Same call with the signed payment (an EIP-3009 authorization, EIP-712 signed: it cannot be
#    typed by hand). x-payment is accepted as the v1 alternative. HTTP 200 carries payment-response.
curl -i -X POST 'https://grist.tools/v1/html-clean-text' -H 'content-type: application/json' -H 'payment-signature: <base64 x402 payload>' -d '{"url":"https://grist.tools/samples/web/render-article.html","include_links":true,"readability":true,"max_chars":2000}'