agent-proxy.alchemypreview.com · echo

echo

Call it in 30 seconds

// This service settles on Base Sepolia.
// Use an x402 client with a matching signer (e.g. an @x402 Solana client).
// First, inspect the payment terms for free:
const r = await fetch("https://agent-proxy.alchemypreview.com/v1/x402-testnet/ceef02c90939785a/echo/"); // returns HTTP 402 + machine-readable terms
console.log(r.status, await r.json());

# This service settles on Base Sepolia.
# Use an x402 client with a matching signer. To see the terms first, for free:
import httpx
r = httpx.get("https://agent-proxy.alchemypreview.com/v1/x402-testnet/ceef02c90939785a/echo/")  # HTTP 402 + machine-readable payment terms
print(r.status_code, r.json())

# 1) An unpaid request returns HTTP 402 with the exact payment terms:
curl -i -X POST "https://agent-proxy.alchemypreview.com/v1/x402-testnet/ceef02c90939785a/echo/" \
  -H 'content-type: application/json' \
  -d '{"message": ""}'

# 2) Paying + retrying requires an x402 client that can sign the USDC
#    authorization (curl alone cannot). See the JS / Python tabs below.

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