The idea of machines paying machines has gone from science fiction to reality. A total of 138.5 million payments have been made on Base using x402, a payment protocol built for AI agents, according to an Oct. 14 report by Chainalysis. That’s up from 58,800 total transactions as of Q3 2025.

AI agent payments look like the next big growth driver in the crypto market, and Solana (SOL -2.75%) is one of the crypto investments best positioned to benefit.

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How x402 enables AI agent payments

First, it’s worth quickly explaining x402. Developed by Coinbase (COIN -2.74%), x402 is a payment protocol that uses the web’s “402 Payment Required” code to attach payment terms to a protected digital resource, such as an API…