--- name: rigc description: Author, build and validate Spine 4.3 skeleton data (skeleton.json plus its .atlas) from loose part PNGs with rigc, the rig compiler that verifies its own output through a spine-core round-trip before writing it. Use for any request to make a Spine rig or Spine animation from PNG parts, to run or read rigc build, validate, render, preview, check or vote, or to write or fix a *.rig.json or *.motion.json spec; it says which shipped guide to open for the need at hand. Not for Live2D conversion, cutting an illustration into parts, or real-time face tracking. license: MIT compatibility: Requires Bun 1.2 or later. The tool is the npm package spine-rigc (bunx spine-rigc, or bun add -d spine-rigc); the command it installs is rigc. --- # rigc — a rig compiler for agents rigc compiles a rig spec and a motion spec into Spine 4.3 skeleton data and an atlas, round-trips the result through `@esotericsoftware/spine-core`, runs its named assertions, and writes **only if every one is green**. You cannot see the rig you are authoring. The validator's messages and the shipped guides are the whole interface, and this skill only says which of them to open. ## Non-negotiables - **Validation is never bypassed.** `build` writes nothing on a red gate; there is no `--no-validate`, and none may be added — AUTHORING §0 says so in as many words. Correctness is the whole of the reason: the round trip through the official parser is the only thing that makes the output trustworthy. - **The compiler never invents a value.** A field the spec leaves out is a `CompileError` naming that field. Fill the spec; do not expect a default read off the art — AUTHORING §2 and §5. - **The validator's messages are the instructions.** Each names the object, the value found and the value required, and AUTHORING §5 maps every named failure to the file that has to change. - **A green gate cannot see a wrong animation.** If you were given pictures, `check` is the half of the loop that can; if not, `render` or `preview` and look — AUTHORING §0 and §9. ## Install ```shell bunx spine-rigc --help # run it without installing bun add -d spine-rigc # or pin it in the project; the command is `rigc` bun rigc skills install # then link these skills into .agents/skills ``` Codex, Gemini CLI and Antigravity read skills from `.agents/skills/` in the workspace and none of them reads `node_modules`; `rigc skills install` puts every skill the package ships there, and `rigc skills --help` says what it refuses. ## The loop 1. `rigc build --rig --motion --images --out ` compiles, gates, and writes only on green. 2. Read the report. Every red line names the file to change; fix the spec and build again. 3. `rigc explain --rig --motion --out ` when the red line is not enough — the compiled rig as a table: every bone with its resolved parent, the slots in draw order, every timeline key by key, and a `DEFORM` block per deform key. It takes no `--profile`, it never gates, and it writes nothing, so the figures are readable on a build the gate is refusing — AUTHORING §0 and §4.11.2. 4. `rigc render --candidate ` or `rigc preview --candidate ` — look at it. A rig with its head off its torso passes the gate; looking is what catches it. 5. `rigc check --candidate --frames ` when you have reference pictures; `rigc vote --candidate --candidate ` when several candidates are green and only a person can choose between them. 6. `rigc validate ` re-gates artifacts already on disk, and `rigc --help` is each command's own flag table. The loop in full, with `pose` before it and `chainfit` after the first build: AUTHORING §0. ## Which guide, for which need Read [AUTHORING.md](https://github.com/firejune/rigc/blob/main/docs/AUTHORING.md) first, whatever the need: the two spec files field by field, the emission rules, the loop, and the failure map. Then: | The request is… | Open | Skill | | --- | --- | --- | | a **skeleton** — how many bones, where each pivot sits, what hangs off what | [RIGGING.md](https://github.com/firejune/rigc/blob/main/docs/RIGGING.md) | `rigc-rigging` | | a **movement** — an idle, a loop, from this pose to that one | [MOTION.md](https://github.com/firejune/rigc/blob/main/docs/MOTION.md) | `rigc-motion` | | a **face** — a blink, a gaze, a head turn a few degrees off axis | [FACE.md](https://github.com/firejune/rigc/blob/main/docs/FACE.md) | `rigc-face` | | a **skeleton.json somebody else authored** — read it, repair it, extend it | [INGEST.md](https://github.com/firejune/rigc/blob/main/docs/INGEST.md) | `rigc-ingest` | | you are the **person operating** the agent rather than the agent | [PROMPTING.md](https://github.com/firejune/rigc/blob/main/docs/PROMPTING.md) | — | 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/`. Formats, the CLI reference and the licence chain: [README.md](https://github.com/firejune/rigc/blob/main/README.md), installed at `node_modules/spine-rigc/README.md`.