The Umlaut APIs are a key element in making Umlaut suitable for using as a central service for known-item features, as described in my earlier blog post Rethinking the Role of an OpenURL link resolver.
On top of APIs, there is a javascript helper to make it as easy as possible to add Umlaut generated content to a known item page in an external application. It’s this javascript helper that I use to embed Umlaut in my OPAC (going live soon, at which point I’ll give you all a tour of the features).
To add Umlaut content to a page, you still need to take care of some tricks related to the particular host environment (such as your OPAC)–you need to generate an OpenURL context object for the particular known-item at hand, somehow, and put it in a javascript variable value. You need to get divs added to the page to stick umlaut content in. But if you can handle these, the javascript helper will take care of the rest.
The APIs and the javascript helper now have some documentation on the umlaut wiki, which some may find interesting whether or not they plan to use Umlaut, as an example of how you might want such an interface to work. (At least, if you are me. :) ).
Bibliographic Wilderness 