The deployment for new Internet services is limited by existing service creation platforms which can be characterized as closed, vertical and best effort in nature. We believe there is a need to develop a programmable Internet built on a foundation of open service interfaces and middleware technologies. To help speed the introduction of value-added services, we propose a unified, programmable Quality of Service (QoS) API framework based on the IEEE P1520 Reference Model fostering open, standard interfaces for networks. We argue that this is a necessary evolutionary step towards a QoS-flexible, Internet service platform. We propose the design of APIs for upper level network QoS be based on service-dependent and service-independent abstractions, supporting alternative styles of QoS specifications and provisioning. Additionally, we propose the design of low-level network element APIs be based on the notion of a building block hierarchy and the separation of service-specific and resource abstractions for the creation and deployment of network services.