API Keys Are Dead. Nanopayments Killed Them.

Your API has a pricing problem. A free tier that costs you money. A paid tier nobody upgrades to. Rate limits that break real use cases. API keys that expire, rotate, and kill production at 3am. Here's what replaces all of it. Agent hits your endpoint. Gets HTTP 402. Pays $0.000001 USDC. Gets the data. No account. No key. No monthly invoice. Just usage. Just revenue. Circle's Agent Marketplace works this way right now. Per-tool USDC pricing. Sellers set a price. Buyers pay per request. No subscription tier to design. No free trial to abuse. You stop managing keys. Your API becomes a vending machine. Every call earns. Part 2 in comments.