The article discusses the challenges faced when integrating AI into a product and how to manage capacity with flow control. It highlights three main problems that arise from building with AI: dealing with users, dealing with the API, and controlling costs. To address these issues, the author suggests using throttling, concurrency, debounce, chaining, and prioritization techniques. These methods help in managing rate limits, ensuring a good user experience, and reducing costs. The article also provides examples of how Inngest can be used to implement these techniques effectively.