Arbitrum now supports x402 and MPP for agentic payment flows. The Arbitrum post says Coinbase's hosted x402 facilitator supports Arbitrum, while Offchain Labs published an open-source Arbitrum implementation for MPP. The goal is to let applications and agents request, verify and settle payments without every builder creating the full payment infrastructure alone.

This matters because AI agents need more than wallets if they are going to pay for APIs, services or digital tasks. They need repeatable payment patterns that can connect web requests to blockchain settlement.

The second-order risk is authorization design: if agents can pay automatically, weak spending limits, replay protection or request binding can turn a useful payment rail into a new attack surface.

Next, watch real developer adoption and the security model around agent spending.