Some documentation on the state of "Helpers"/Gadgets/Widgets etc. is at Helpers and Gadgets within Sakai. This page describes a particular implementation strategy for the markup-based "AHAH"-style helpers which are described there, which make use of RSF and the EntityBroker. This strategy for navigation interception is also known as Hijax.
Neither RSF nor the EntityBroker are required to adopt this strategy, nor need it particularly refer to "helpers" which are hosted within the Sakai server at all. RSF is illustrated because it is a technology which is now popular for new development in Sakai, and in which these techniques are quite easy. The EntityBroker is used, since as described on the Helpers, it is a good scheme for achieving short, semantically meaningful and architecturally decoupled URLs for application segments in Sakai, which are also meaningful when dispatched outside it. Use of the EntityBroker does not imply the use of RSF, but there is a standard framework integration between these technologies.
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