Houdini has Character Picker and Pose Library (anim lib) tools for object level rigging, but not yet for KineFX SOP level rigging. So I have implemented my version of these tools for Kevfx Biped Auto-Rig.
It is still in the early development stage with first versions released to Orbolt.com (the official Houdini App store).
The core tool of the Anim Lib is the Kevfx Keyframe Cache node, which can collect keyframes from nodes or Animation Editor, cache keyframes to disk files, and copy keyframes to other nodes. The good thing about this node is that it deals with real keyframes, and will NOT sample the animation at every single frame.
The character picker tools consist of an asset (Kevfx Biped Char Picker) and a UI (a pane tab which is Python Panel). The asset needs to be in the scene for the UI to work. And the UI can be installed to users' Houdini via the asset.
