From their site: Harvest provides two API interfaces, serving two distinct roles. If you need to access and manipulate your daily timesheet the Timetracking API fits the bill. Notable uses are the widgets we provide for PC and Mac as well as other third party timesheet software integrations. If you need to access and edit your projects, clients, users and tasks the Extended REST API is your choice. You can use this to mass import your existing projects setup, add users and generally integrate with your existing back-office setup.
The following is a list of SDKs from our SDK directory that matched your search term. Though your definition of an SDK may differ, in our world, we define SDKs as platform- specific tools for consuming existing APIs of the sort we list in our API directory. For example, the Ruby SDK for consuming the Twitter Ads API. If you think an SDK, API, or other asset is missing from our directory, be sure to check our guidelines for making contributions to ProgrammableWeb.