Google today launched the Google API Explorer, a tool that lets developers explore the application programming interfaces the company has made available and even test the API functions without leaving the app.

The API Explorer supports the Buzz, Custom Search, Diacritize, Moderator, Shopping, Translate and URL Shortener APIs. Google plans to make more available fairly quickly.

“Today, the Explorer supports over a half dozen APIs – and we expect that number to grow rapidly over the coming weeks and months,” said the developers in a Google Code blog post.

Google has long made APIs for its services available, but the new tool makes discovering features that developers might not have known about easy, and the ability to enter parameters and test functions will surely be a timesaver for developers who are getting acquainted with the APIs.