Text Diff

{
  "added": 2,
  "asOf": "2026-10-12T00:50:08.724Z",
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "edits": [
    {
      "count": 2,
      "op": "equal",
      "text": "the quick"
    },
    {
      "count": 1,
      "op": "delete",
      "text": "brown"
    }
  ],
  "notChecked": [
    "moved blocks: a moved line shows as a delete plus an insert",
    "when several minimal diffs exist, one is returned (deletes before inserts)",
    "…1 more"
  ],
  "ratio": 0.6667,
  "reasons": [
    "Similarity ratio = 2 * unchanged / (units in A + units in B), the same definition as Python difflib's ratio."
  ],
  "removed": 1,
  "source": "computed locally (longest-common-subsequence diff)",
  "summary": "1 word removed, 2 added, 3 unchanged.",
  "unchanged": 3,
  "unit": "word",
  "unitsA": 4,
  "unitsB": 5,
  "verdict": "CHANGED"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://text-similarity.x402tookit.com/text-diff?a=the+quick+brown+fox&b=the+quick+red+fox+jumps&unit=word'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://text-similarity.x402tookit.com/text-diff?a=the+quick+brown+fox&b=the+quick+red+fox+jumps&unit=word' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

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

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Ftext-similarity.x402tookit.com%2Ftext-diff
const res = await pay("https://text-similarity.x402tookit.com/text-diff?a=the+quick+brown+fox&b=the+quick+red+fox+jumps&unit=word");
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://text-similarity.x402tookit.com/text-diff?a=the+quick+brown+fox&b=the+quick+red+fox+jumps&unit=word")
    print(res.status_code, res.text)