The WorldCat Idententies API mines the Worldcat database for individual identities and creates a page for each identity. Response include related ISBN's or other identifiers, as well as metadata. If you have heard of xISBN, xISSN, or xOCLCnum APIs, this is comprised of those.
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.