Sentiment

{
  "mode": "sentiment",
  "paid_sats": 20,
  "payment_hash": "x402:<sha256 hex>",
  "receipt": {
    "payload": {
      "at": "<ISO 8601 time>",
      "kid": "<signing key id>",
      "mode": "sentiment",
      "payment_hash": "x402:<sha256 hex>",
      "v": 1,
      "verdict_sha256": "<sha256 hex of the verdict>"
    },
    "signature": "<base64url Ed25519 signature>"
  },
  "verdict": {
    "aspects": [
      {
        "aspect": "product",
        "label": "very_positive",
        "mentioned": true,
        "score": 1
      },
      {
        "aspect": "price",
        "label": "very_negative",
        "mentioned": true,
        "score": -1
      },
      {
        "aspect": "support",
        "label": "very_negative",
        "mentioned": true,
        "score": -1
      }
    ],
    "confidence": 0.88,
    "decision": "negative",
    "label": "negative",
    "mixed": true,
    "rule": "score from -1 (very negative) to +1 (very positive) ; uncertain if confidence < 0.6 ; an aspect that is not mentioned is not scored (mentioned >= 0.5)",
    "score": -0.5
  }
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://verdict.kechlab.com/v1/sentiment' \
  -H 'content-type: application/json' \
  --data-raw '{"aspects":["product","price","support"],"text":"The product is great but the price is too high and support never answered."}'

# 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 - -X POST 'https://verdict.kechlab.com/v1/sentiment' \
  -H 'content-type: application/json' \
  --data-raw '{"aspects":["product","price","support"],"text":"The product is great but the price is too high and support never answered."}' \
  | 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 $0.0172 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.0172" });
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 $0.0172 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fverdict.kechlab.com%2Fv1%2Fsentiment&method=POST
const res = await pay("https://verdict.kechlab.com/v1/sentiment", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "aspects": [
      "product",
      "price",
      "support"
    ],
    "text": "The product is great but the price is too high and support never answered."
  }),
});
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 $0.0172 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.0172"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://verdict.kechlab.com/v1/sentiment",
        json={
            "aspects": [
                "product",
                "price",
                "support",
            ],
            "text": "The product is great but the price is too high and support never answered.",
        },
    )
    print(res.status_code, res.text)