First Call — x402 Payment Endpoint

The canonical starting point for AI agents integrating with Coin Railz. Pay $0.05 USDC on Base or Solana to confirm your x402 payment stack works end-to-end — then follow the 5 executable next-service calls in the response to make your first real data call immediately.

Chains Accepted

How It Works

Send a POST request without a payment header to receive a 402 challenge containing full dual-track payment instructions — EVM via Coinbase CDP facilitator, Solana via Dexter (x402.dexter.cash). Submit payment and include the receipt in the X-PAYMENT header on your next request to receive your onboarding receipt.

Quick Start

curl -X POST https://coinrailz.com/x402/first-call \
  -H "Content-Type: application/json" \
  -d '{}'

# Returns HTTP 402 with full payment instructions.
# Submit payment, then:

curl -X POST https://coinrailz.com/x402/first-call \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <your_payment_receipt>" \
  -d '{}'

What You Get Back

{
  "service": "x402 Golden Path — First Paid Call",
  "sessionId": "gp-...",
  "payment": { "verified": true, "amount": "0.05 USDC" },
  "nextServices": [ ... 3 ready-to-run templates ... ],
  "partnerContact": { "email": "support@coinrailz.com" }
}

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