The present page serves as an overview for the topic. All available documents for the topic can be found here.
Intershop's Omni-Channel Services Toolset is a collection of frameworks that enable fast, standardized development of business web apps like the Intershop Contact Center. Based on open-source technologies, the OCST is decoupled from the Intershop Commerce Management core platform and uses the REST API (as part of the Synaptic Commerce API) to access data and commerce functionality.
For details about the REST API see: Reference - Omni-Channel Services Toolset REST API.