name: rigc-motion description: Author a Spine animation with rigc from key poses — an idle, a loop, a move from one picture to another — with timing and spacing, ease in and out, anticipation, arcs, overlap, follow-through, squash and stretch, and candidate variants a person can choose between. Use when the request is a movement on an existing or planned rig, in the animator's words too: "animate this rig", "make it breathe", "go from pose A to pose B", "make it feel heavier", "the cape should follow through". Not for Live2D, separating an image into parts, or real-time tracking. license: MIT compatibility: Requires Bun 1.2 or later and the npm package spine-rigc.
Motion — what goes between two poses
Load this when the request is a movement rather than a skeleton: a sentence of intent, between zero and N pictures of what the movement passes through, and a Spine animation somebody would choose coming back. Every rule below is owned by MOTION.md; this file says when to open it and what it will not do for you.
Non-negotiables
- Validation is never bypassed.
buildwrites nothing on a red gate, and there is no flag that changes that — AUTHORING §0. - The compiler never invents a value. A key with no time, a curve with no kind, a bone the rig does not declare — each is refused by name before anything is written — AUTHORING §4 and §6.
- The validator's messages are the instructions. Read each named failure as the pointer to the file that has to change — AUTHORING §5.
What this guide will not do
Nothing here grades a movement, and no instrument named here can. build says a
file is valid, check says how far it is from pictures you were given, and the one
thing that judges a movement is a person's eye through rigc vote — MOTION §0.
Read, in this order
- AUTHORING.md — the motion spec field by field (§4), the failure map (§5–§6), reading reference frames (§8) and checking against them (§9), what the editor does when nobody tells it otherwise (§10), and reading a pose out of a picture (§11–§12).
- MOTION.md — the normal form every motion request reduces to (§0), timing, easing and the per-bone offset table (§3), and how to spread candidates so a ballot informs (§4–§5).
- Then RIGGING.md if the skeleton itself is what you have to decide; FACE.md if the movement is a blink, a gaze or a head turn; INGEST.md if the rig arrived as a compiled skeleton rather than loose parts.
Every guide linked here is in the installed package at node_modules/spine-rigc/docs/,
which is the copy that matches the rigc you run; the links go to the repository's
main. Inside the Claude Code plugin the same files are at ${CLAUDE_PLUGIN_ROOT}/docs/.
The install line and the build → validate → render → check loop are in the rigc
skill.