Coinbase x402 Protocol Expands ERC-20 Support, Sign-in-with-X, and MCP Monetization

x402 expands ERC-20 support, adds Sign-in-with-X for wallet access, and enables MCP monetization across EVM and Solana wallets.

Rich by Coin

2026-03-17

Coinbase’s x402 protocol now supports all ERC-20 tokens, enabling on-chain payments for tokens including USDC, EURC, and Memecoin via EIP-3009 and Permit2. The platform introduces a Sign-in-with-X feature that lets buyers access purchased content via wallet login, and allows sellers to grant payment-free access to returning customers, with support for both EVM and Solana wallets. In addition, the x402 MCP package has been released, allowing developers to monetize any MCP tool and directly integrate it into AI workflows. These enhancements are designed to cement x402 as the most flexible and open internet-native standard for on-chain payments and cross-wallet interoperability.

This expansion enhances token interoperability and positions x402 as a flexible, internet-native standard for on-chain transactions. This feature set strengthens cross-wallet usability and improves user re-engagement across ecosystems.

The release of the x402 MCP package enables developers to monetize any MCP tool and directly integrate it into AI workflows. These updates reinforce x402 as a comprehensive framework for on-chain payments, cross-wallet interoperability, and seamless developer tooling in Web3.