Frequently Asked Questions
Everything you need to know about Buildx402
What is x402?
x402 is an open payment standard that uses the HTTP 402 "Payment Required" status code to enable autonomous microtransactions for AI agents and APIs. It allows agents to pay for API calls automatically using cryptocurrencies like USDC, eliminating the need for subscriptions or API keys.
How do x402 agents work?
x402 agents make API calls like normal requests. When an API requires payment, it returns HTTP 402 with payment details. The agent automatically pays using USDC from its wallet, then retries the request with payment proof. The API verifies payment and returns the data.
What networks are supported?
We support multiple networks: Base (recommended for low fees), Ethereum, Polygon, Arbitrum, and Solana. All payments use USDC stablecoin. You can create agents on any of these networks.
Do I need to manually approve each payment?
No! That's the beauty of x402 agents. You can set them to auto-approve payments up to a maximum amount you specify. Agents handle payments autonomously without manual intervention.
How much does it cost to use x402 agents?
There are no platform fees. You only pay for the API calls your agents make. Each API sets its own pricing, and your agent pays per request. You can set maximum payment limits to control spending.
What happens if my agent runs out of USDC?
If your agent's wallet doesn't have enough USDC for a payment, the API call will fail. You can monitor your agent's balance and add more USDC to the wallet as needed.
Are payments secure?
Yes! All payments are made on-chain using USDC, which is fully transparent and verifiable. You control the wallet private key, and agents only have access to make payments from that wallet.
Can I use x402 agents with any API?
x402 agents work with any API that implements the x402 protocol (returns HTTP 402 with payment headers). The API must be x402-compatible. Many APIs are adding x402 support.
What can I build with x402 agents?
You can build AI assistants, data fetching bots, trading bots, automation workflows, analytics agents, and more. Any application that needs to pay for API calls can benefit from x402 agents.
How do I get started?
1. Connect your wallet (MetaMask for EVM chains like Base/Ethereum/Polygon/Arbitrum, or Phantom for Solana) with USDC. 2. Create an agent using the agent builder and select your preferred network. 3. Configure your agent's settings (max payment amount, auto-approve, etc.). 4. Start your agent and let it work autonomously!
Can I pause or stop my agents?
Yes! You have full control. You can pause agents at any time, which stops them from making API calls. You can also delete agents if you no longer need them.
Is there a limit to how many agents I can create?
No, there's no limit. Create as many agents as you need. Each agent operates independently with its own wallet and configuration.