HTTP 402 is a status code that has existed since 1991. “Payment Required.” Reserved for a future where machines could pay for things. Nobody used it. Digital money didn’t exist yet.
Thirty-five years later, three protocols are racing to claim it.
L402 runs on Lightning. x402 is backed by Coinbase. MPP launched last month with Anthropic and Stripe at the table. Fifteen thousand paid API endpoints now live in a directory with hourly health checks, built specifically so AI agents can discover, verify, and pay for data.
The agents are already buying. Fifty-eight percent of live traffic goes to real-time data feeds — DeFi yields, token anomalies, security intelligence. Things that change every block. The agents aren’t browsing. They’re transacting.
The infrastructure Bitcoin advocates built for human sovereignty is going to be used by machines first. That was not the plan. It may be the best possible outcome.
The protocol that waited thirty years finally has a customer.