Stripe's investment letter has been leaked—OpenRouter might be the Alipay + cloud service gateway of the AI era. Yesterday’s leaked Stripe investor letter revealed: OpenRouter will join Stripe, marking Stripe’s largest acquisition ever. Many people’s first reaction: An AI model API aggregation platform—is it really worth Stripe spending big money? But looking at it from another angle, OpenRouter might actually be one of the most critical gateways in the AI Agent era. What does Stripe want when AI Agents start making real money? They need identity. They need wallets. They need payment systems. They need automated settlements. They need to purchase computing power and services. This is exactly what Stripe is building. OpenRouter handles the AI brain’s operations. Stripe handles how the AI’s money flows. So this feels more like building an AI economic system in advance: In the future, there could be hundreds of millions of Agents replacing humans to complete tasks, and Stripe wants to be the bank, payment network, and infrastructure for these Agents. Over the past 20 years, internet giants competed for user gateways. In the next 10 years, the competition might be for the economic gateways of AI Agents. OpenAI is building the brains, NVIDIA is selling computing power, and Stripe is going after the wallets of the AI world.