Animation Tools is a Blender add-on that collects a range of keyframe and pose utilities aimed at streamlining common, tedious animation tasks. It brings functions like Push Keyframes, Move Keyframes to a set frame, Add Keyframe Value, Clean Keyframes, and Set Keyframe Interval together in one panel, which is available in the 3D viewport and, since the V1.01 update, the graph editor.
On the keyframe side, Push Keyframes shifts selected keys along the timeline by any interval, Clean Keyframes strips out redundant matching keys and can also trigger Blender's built-in decimate, and Set Keyframe Interval places stepped keys at your chosen spacing with a selectable interpolation type. Loop Selected repeats keyframes a set number of times, and Select all Curves grabs every fcurve, keyframe, and handle straight from the viewport.
For rigged characters, it adds Copy Bone Position across a frame range, Keyframe all Bones on shared frames, Reset Bones, Flip Pose, and Constrain Objects to Bones. Motion Paths and Onion Skin round out the set, and many tools are reachable through a pie menu on the customizable 'e' hotkey.