Pay with x402 (USDC on Solana) — for AI agents

curl -si https://getvibeapi.com/v1/models

HTTP/2 402
content-type: application/json
payment-required: eyJ4NDAyVmVyc2lvbiI6Mi…   (base64 JSON, below)

{
  "error": {
    "message": "Top up with USDC on Solana: register your wallet first (sign the challenge, POST it to /api/x402/verify), then send at least $1 USDC to 9N5KTgRBfGarFVrJJi1KQg8qoD393rayWBjf1ejXRrkc. Register your wallet BEFORE paying: sign the sign-in-with-x challenge with the Solana wallet you will pay from and POST it to /api/x402/verify. Then send USDC on Solana from that same wallet (you must control its private key), and POST a freshly signed challenge to /api/x402/verify again to receive your API key. Deposits from a wallet that was not registered first, or from an exchange or any other custodial wallet, are not credited automatically and require manual operator review.",
    "type": "insufficient_quota",
    "code": 402,
    "cause": "missing_key",
    "x402": {
      "payTo": "9N5KTgRBfGarFVrJJi1KQg8qoD393rayWBjf1ejXRrkc",
      "asset": "USDC",
      "network": "solana",
      "minDepositUsd": 1,
      "docs": "https://getvibeapi.com/docs/x402"
    },
    "request_id": "…"
  }
}

curl -s -D - -o /dev/null https://getvibeapi.com/v1/models \
  | awk 'tolower($1)=="payment-required:"{print $2}' | tr -d '\r' | base64 -d | jq

{
  "x402Version": 2,
  "error": "Payment required. First sign the sign-in-with-x challenge with your wallet and POST it to /api/x402/verify (registers the wallet), then send at least $1 USDC (mint EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v) on Solana from that wallet to the payTo address, then sign in again for your API key.",
  "resource": { "url": "https://getvibeapi.com/v1/models", "description": "…", "mimeType": "application/json" },
  "accepts": [{
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "amount": "1000000",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "payTo": "9N5KTgRBfGarFVrJJi1KQg8qoD393rayWBjf1ejXRrkc",
    "maxTimeoutSeconds": 600,
    "extra": { "name": "USDC", "decimals": 6, "depositWarning": "…", "docs": "https://getvibeapi.com/docs/x402" }
  }],
  "extensions": {
    "sign-in-with-x": {
      "info": {
        "domain": "getvibeapi.com",
        "uri": "https://getvibeapi.com/v1/models",
        "version": "1",
        "nonce": "…",
        "issuedAt": "…",
        "expirationTime": "…",
        "statement": "Sign in to register this Solana wallet with your GetVibe API account. Only continue if you control this wallet. USDC is credited automatically only when it is sent from a wallet registered before the payment; deposits from an exchange or other custodial wallet cannot be linked to an account.",
        "resources": ["https://getvibeapi.com/v1/models"]
      },
      "supportedChains": [{ "chainId": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp", "type": "ed25519", "signatureScheme": "siws" }]
    }
  }
}

curl -s https://getvibeapi.com/api/x402/challenge \
  -H "Content-Type: application/json" \
  -d '{"wallet":"9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM"}'

{
  "ok": true,
  "wallet": "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM",
  "message": "getvibeapi.com wants you to sign in with your Solana account:\n9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM\n\nSign in to register this Solana wallet with your GetVibe API account. Only continue if you control this wallet. USDC is credited automatically only when it is sent from a wallet registered before the payment; deposits from an exchange or other custodial wallet cannot be linked to an account.\n\nURI: https://getvibeapi.com/v1\nVersion: 1\nChain ID: 5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp\nNonce: 684c31b4bc2b7709b95d61dcb5a03fea\nIssued At: 2026-09-27T13:57:32.210Z\nExpiration Time: 2026-09-27T14:02:32.210Z\nResources:\n- https://getvibeapi.com/v1",
  "signInWithX": {
    "info": {
      "domain": "getvibeapi.com",
      "uri": "https://getvibeapi.com/v1",
      "version": "1",
      "nonce": "684c31b4bc2b7709b95d61dcb5a03fea",
      "issuedAt": "2026-09-27T13:57:32.210Z",
      "expirationTime": "2026-09-27T14:02:32.210Z",
      "statement": "Sign in to register this Solana wallet with your GetVibe API account. Only continue if you control this wallet. USDC is credited automatically only when it is sent from a wallet registered before the payment; deposits from an exchange or other custodial wallet cannot be linked to an account.",
      "resources": ["https://getvibeapi.com/v1"]
    },
    "supportedChains": [{ "chainId": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp", "type": "ed25519", "signatureScheme": "siws" }]
  },
  "warning": "Register your wallet BEFORE paying: sign the sign-in-with-x challenge with the Solana wallet you will pay from and POST it to /api/x402/verify. Then send USDC on Solana from that same wallet (you must control its private key), and POST a freshly signed challenge to /api/x402/verify again to receive your API key. Deposits from a wallet that was not registered first, or from an exchange or any other custodial wallet, are not credited automatically and require manual operator review.",
  "expiresAt": "2026-09-27T14:02:32.210Z"
}

curl -s https://getvibeapi.com/api/x402/verify \
  -H "Content-Type: application/json" \
  -d '{
    "domain": "getvibeapi.com",
    "address": "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM",
    "uri": "https://getvibeapi.com/v1",
    "version": "1",
    "chainId": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "type": "ed25519",
    "signatureScheme": "siws",
    "nonce": "684c31b4bc2b7709b95d61dcb5a03fea",
    "issuedAt": "2026-09-27T13:57:32.210Z",
    "expirationTime": "2026-09-27T14:02:32.210Z",
    "statement": "Sign in to register this Solana wallet with your GetVibe API account. Only continue if you control this wallet. USDC is credited automatically only when it is sent from a wallet registered before the payment; deposits from an exchange or other custodial wallet cannot be linked to an account.",
    "signature": "<base58 ed25519 signature of message>"
  }'

{
  "ok": true,
  "wallet": "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM",
  "key": "sk-pv-…",
  "type": "payg",
  "note": "Store this key securely. Every subsequent request uses it like any other API key."
}

curl https://getvibeapi.com/v1/chat/completions \
  -H "Authorization: Bearer $GETVIBE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-6.1-sol","messages":[{"role":"user","content":"Hello"}]}'

curl https://getvibeapi.com/v1/balance -H "Authorization: Bearer $GETVIBE_API_KEY"
# {"balance": 1, "currency": "USD", ...}

import { Connection, Keypair, PublicKey, Transaction, sendAndConfirmTransaction } from '@solana/web3.js';
import { createTransferCheckedInstruction, getOrCreateAssociatedTokenAccount } from '@solana/spl-token';
import nacl from 'tweetnacl';
import bs58 from 'bs58';

const API = 'https://getvibeapi.com';
const USDC_MINT = 'EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v';
const wallet = Keypair.fromSecretKey(bs58.decode(process.env.SOLANA_SECRET_KEY!));
const connection = new Connection(process.env.SOLANA_RPC_URL ?? 'https://api.mainnet-beta.solana.com', 'confirmed');
const sleep = (ms: number) => new Promise((r) => setTimeout(r, ms));

// Sign a fresh challenge with the wallet and post it to /api/x402/verify.
async function signAndVerify(): Promise<Response> {
  const address = wallet.publicKey.toBase58();
  const challenge = await fetch(`${API}/api/x402/challenge`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ wallet: address }),
  }).then((r) => r.json());
  const signature = bs58.encode(nacl.sign.detached(new TextEncoder().encode(challenge.message), wallet.secretKey));
  const chain = challenge.signInWithX.supportedChains[0];
  return fetch(`${API}/api/x402/verify`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      ...challenge.signInWithX.info,
      address,
      chainId: chain.chainId,
      type: chain.type,
      signatureScheme: chain.signatureScheme,
      signature,
    }),
  });
}

// 1. Read the payment requirements from the 402.
const probe = await fetch(`${API}/v1/models`);
if (probe.status !== 402) throw new Error(`expected 402, got ${probe.status}`);
const required = JSON.parse(Buffer.from(probe.headers.get('payment-required')!, 'base64').toString('utf8'));
const accept = required.accepts[0];
if (accept.asset !== USDC_MINT || !accept.network.startsWith('solana:')) throw new Error('unexpected asset/network');

// 2. Register the wallet BEFORE paying: a verified signature marks it as an expected payer.
const registered = await signAndVerify();
const reg = await registered.json();
if (registered.status !== 402 || reg.error?.cause !== 'x402_wallet_registered_awaiting_deposit') {
  throw new Error(`registration failed: ${registered.status} ${JSON.stringify(reg)}`);
}

// 3. Pay at least the minimum (here: exactly the minimum) from the SAME wallet.
const mint = new PublicKey(accept.asset);
const amount = BigInt(accept.amount);
const from = await getOrCreateAssociatedTokenAccount(connection, wallet, mint, wallet.publicKey);
const to = await getOrCreateAssociatedTokenAccount(connection, wallet, mint, new PublicKey(accept.payTo));
const tx = new Transaction().add(
  createTransferCheckedInstruction(from.address, mint, to.address, wallet.publicKey, amount, accept.extra.decimals),
);
const txSignature = await sendAndConfirmTransaction(connection, tx, [wallet], { commitment: 'finalized' });
console.log('paid', txSignature);

// 4–5. Sign a fresh challenge until the deposit is credited, then keep the key.
async function getApiKey(): Promise<string> {
  for (let attempt = 0; attempt < 30; attempt++) {
    const res = await signAndVerify();
    if (res.ok) return (await res.json()).key;
    if (res.status !== 402) throw new Error(`verify failed: ${res.status} ${await res.text()}`);
    await sleep(30_000); // deposit not credited yet
  }
  throw new Error(`deposit ${txSignature} not credited after 15 minutes — contact [email protected]`);
}

const apiKey = await getApiKey(); // store it securely: it is shown once

// 6. A normal OpenAI-compatible call.
const reply = await fetch(`${API}/v1/chat/completions`, {
  method: 'POST',
  headers: { Authorization: `Bearer ${apiKey}`, 'Content-Type': 'application/json' },
  body: JSON.stringify({ model: 'gpt-6.1-sol', messages: [{ role: 'user', content: 'Hello' }] }),
}).then((r) => r.json());
console.log(reply.choices[0].message.content);