The Tapir API is really 3: Search, Ping and Post to give you the power to make your blog searchable, get your articles indexed immediately, and push content manually. Indexing of the Rss feed is done at 15 minute intervals. According to the API documentation, the results are returned in JSON or JSONP.
As the website Killerstartups explained, "All the content that you post to your blog from that point onwards will be indexed every 15 minutes. And old articles will also be indexed."
A post by Jeff Kreeftmeijer spells out why Tapir can be a useful alternative to Google and other search engines for your website.
"A feature I really wanted in my website was search, since the archive grew quite a bit and it became impossible to find an article without knowing its title, so I started looking for a solution I could use."
Kreeftmeijer continues, "After asking around, it turned out Google’s custom search is still the most used out there. The problem I ran into was that it takes you off the website you were searching on and takes you to a Google results page (complete with slightly irrelevant ads).
Commenting on the post someone calling themselves Vancouver Web Design, concurred, saying: "This is awesome I am going to check it out, anyways I am looking for decent search for our CMS, some of our web design clients need a search for their website and Google is not a option since they don't want to have Google logo on their website."