1. The document discusses the importance of companies dogfooding or using their own APIs internally to improve API design and catch issues. 2. It recommends that development teams should only communicate with each other through API interfaces and these interfaces should be designed from the beginning to be externalizable. 3. The document also provides tips for API design such as using versioning, consistent behavior, simplicty, standards, caching and personalized onboarding to improve APIs and user experience.