This is an API to support U2F (Universal Two Factor Authentiation), with hardware devices such as the FIDO security key. The API helps decrypt and verify both registration requests and signing requests on a hardware security key, via the browser.
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.