What is a Cloud API
As enterprises integrated their existing IT infrastructures and resources with the cloud, cloud providers had to provide an API that these enterprises could use to tailor the cloud to their specific needs.
A Cloud Application Programming Interface (Cloud API) is just that as it enables the development of applications and services used for the provisioning of cloud hardware, software, and platforms. It serves as a gateway or interface that provides direct and indirect control over a cloud infrastructure and software services to end users. It is now the core component behind any public cloud solution although the lack of a standard API can make it difficult sometimes.
In a Home Automation system one can extend functionality by writing own software code to interact with a third-party device via its public Cloud API when available.