Tushar Bhushan discusses the challenges of integrating third-party providers in the travel industry and introduces Apollo GraphOS as a solution. He explains how traditional GraphQL approaches have limitations when it comes to visibility of individual field usage and clients accessing them, but Apollo GraphOS streamlines this process by leveraging Contracts, demand control features, and field-level metrics. The author highlights the importance of schema contracts, graph variants, and observability tools in creating a seamless and secure integration experience. He also demonstrates how to implement a contract variant using Apollo Federation's `@tag` directive and GraphOS Contracts, which provides several advantages such as maintaining a single source supergraph implementation while serving different applicable versions of the supergraph to different clients.