This week, AWS launched Bedrock AgentCore with integrated Coinbase and Stripe payments. Visa announced cards designed specifically for AI agents. Sapiom raised $15M to build agent payment rails on existing infrastructure. At the same time, agent-native platforms raised comparable capital to build from scratch. Two camps. Same market. Fundamentally different bets. One side is retrofitting human payment rails for agents. The other is building agent-native infrastructure. Both approaches have $30M+ in backing. But they're solving different problems. If you're building agents that need to transact, the choice matters. Here's the technical breakdown. The Latency Problem Card authorization takes 2-3 seconds. That's acceptable when a human is waiting for a checkout page to load. It's not acceptable when an agent is making 1,000 API calls per hour. Agent-native MPC wallets authorize transactions in <150ms. The difference compounds. At scale, latency isn't an inconvenience — it's a structural bottleneck.…