The Petfinder Python SDK by Greg Taylor allows to access API data to implement animal search features into applications. Full documentation includes key access, shelter query, and pet search. Greg ads find homes for the pets in his TODO.
Search engines such as Google have been making life a lot easier for developers. They have huge development resources that startups just don't have, and when they make their APIs available, everyone benefits. But when it comes to using APIs, especially AJAX APIs, it can be a challenge for developers to use these in a search-friendly way.