x402 for AI Agents

Build AI agents that autonomously discover, evaluate, and pay for blockchain data using the x402 protocol - no API keys or human intervention required.

The x402 protocol was designed with machine-to-machine payments in mind. An AI agent with a funded wallet can autonomously access the full GoldRush API - no signup flow, no credentials to rotate, no billing portal, no human in the loop.

Agent workflow

An AI agent interacting with GoldRush x402 follows four steps:

1. Discover

Call the free discovery API to find available endpoints:

curl https://x402.goldrush.dev/v1/x402/endpoints | jq

The response includes endpoint names, descriptions, credit rates, pricing models, and supported chains - everything an agent needs to decide what to call.

2. Evaluate

Search for relevant endpoints and check pricing before committing:

# Find balance-related endpoints
curl https://x402.goldrush.dev/v1/x402/search?q=balance | jq

# Check pricing for a specific endpoint
curl https://x402.goldrush.dev/v1/x402/endpoints/get-token-balances-for-address | jq

The agent can compare credit rates against its budget and select the right tier for variable-length responses.

3. Pay

Using the x402 client, the agent signs a payment and gets data in a single request-response cycle:

import { x402Client } from "@x402/core/client";
import { ExactEvmScheme } from "@x402/evm";
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client().register("eip155:84532",
  new ExactEvmScheme(privateKeyToAccount(process.env.WALLET_PRIVATE_KEY))
);

const paidFetch = wrapFetchWithPayment(fetch, client);

const response = await paidFetch(
  "https://x402.goldrush.dev/v1/eth-mainnet/address/aave.eth/balances_v2/"
);

const balances = await response.json();

console.log(JSON.stringify({
  headers: Object.fromEntries(response.headers.entries()),
  body: balances,
}, null, 2));

No OAuth, no API key provisioning - the agent just needs a funded wallet.

4. Consume

Responses use the same JSON format as the standard GoldRush API. Any existing parsing logic works unchanged.

Why x402 for agents

Concern	API Key	x402
Provisioning	Requires signup, key management, rotation	Wallet is the credential
Budget control	Monthly plan, overage charges	Pay exactly per request
Human involvement	Account creation, billing setup	None - fully autonomous
Discovery	Read docs or hardcode endpoints	Programmatic endpoint discovery
Multi-agent	Share key or provision per agent	Each agent gets its own wallet

Rate limits

Each wallet is rate-limited to 100 requests per minute. The X-RateLimit-Remaining response header shows how many requests remain in the current window.