The World Wide Web Consortium (W3C) is an international community that works to develop Web standards. The Markup Validation service is offered by the W3C to check the markup validity of Web documents in HTML, XHTML, SMIL, MathML, and more. Developers can use the API to access the functionality of the service and integrate it with their own applications. The API uses SOAP protocol and responses are formatted in XML.
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.