# Animation Creator

> Create character animations from a source image or character description, preserving identity across actions and exporting animated WebP assets.

- Skill: `smturtle2/animation-creator` (Agent Skill, multi-file: 19 files)
- Install (CLI): `npx skillmds@latest add smturtle2/animation-creator`
- Raw SKILL.md: https://api.skillmd.com/api/skills/smturtle2/animation-creator/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: smturtle2 (https://skillmd.com/u/smturtle2)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/smturtle2/animation-creator

---


# Animation Creator

Use one canonical character per run and `$image-creator` for every generated base or action sheet. Do not synthesize character frames with local drawing, tiling, or warping scripts.

Set `SKILL_DIR` to this skill's absolute directory. Run helpers with `uv run --project "$SKILL_DIR"` from the session project root. Keep working files in `.codex-skills/animation-creator/<run-id>/` unless the user chooses another workspace. Use a unique ID for a new run and reuse the existing path when continuing, including older runs elsewhere. Resolve relative input and output paths from the project root.

When creating the default workspace in a Git project, ensure `/.codex-skills/` is ignored unless the user intends to version that data.

## Plan the Action

Establish the character source and requested action; ask for the action if missing. Use requested timing and loop settings, defaulting to a looping WebP with full-body poses. Record an explicit partial-body request as the output contract.

Build adjacent motion beats before choosing a frame count. Each beat after the starting pose should describe the visible change from its predecessor, preserving character scale, facing, body-center path, balance, contact, and weight transfer.

Audit for needed anticipation, contact or launch, passing poses, follow-through, settling, and loop bridge or clear end pose. Remove duplicate silhouettes and tiny redundant steps. The audited beat count becomes the frame count, up to 12. Avoid flip/mirror/rotation language unless the action actually needs that transformation.

## Prepare or Extend

For a new run, read [references/run-setup.md](references/run-setup.md). Preserve the source or generated base as `references/canonical-base.png` without background removal.

For a later action, reuse the run and canonical base unless the user requests a new character:

```bash
uv run --project "$SKILL_DIR" "$SKILL_DIR/scripts/prepare_animation_run.py" \
  --run-dir <run-dir> --add-action --action-id <action-id> \
  --action "<description>" --frame-actions "<beat 1>; <beat 2>; <beat N>"
```

Read [references/animation-output-contract.md](references/animation-output-contract.md) before generating an action sheet when that contract is not already in context. The current pipeline requires `rembg-matte` raw sheets and rembg-normalized alpha outputs.

## Generate and Record

Build the prompt for the base job or selected action:

```bash
uv run --project "$SKILL_DIR" "$SKILL_DIR/scripts/build_generation_prompt.py" \
  --run-dir <run-dir> --job-id <job-id>
```

Give stdout to `$image-creator` as the authoritative final prompt, unchanged, and pass a destination inside this run. Do not rewrite it or maintain a separate `prompts/image-creator/` copy.

For each action, supply both `references/canonical-base.png` as identity input and `references/registration-guides/<action-id>.png` as the edit template. Save attempts under the run's `generated/attempts/` with non-overwriting names.

Inspect the returned raw action sheet against the output contract: fixed grid and slot order, complete poses, reserved matte, retained outer cell borders, removed inner guides, and continuous character identity and motion. Record only a selected image that passes this review:

```bash
uv run --project "$SKILL_DIR" "$SKILL_DIR/scripts/record_animation_result.py" \
  --run-dir <run-dir> --job-id <job-id> --source <saved-source-image>
```

Recording a base preserves it and refreshes action prompts/guides. Recording an action performs per-slot rembg processing and reassembles the alpha sheet. If processing fails, report the error; do not substitute a different background-removal pipeline.

## Finalize and Review

```bash
uv run --project "$SKILL_DIR" "$SKILL_DIR/scripts/finalize_animation_run.py" \
  --run-dir <run-dir> --action-id <action-id>
```

Read [references/qa-rubric.md](references/qa-rubric.md) before acceptance. Review validation results, the contact sheet, and animation where a viewer is available; deterministic checks alone cannot establish identity or motion quality. Repair the failed action or processing step without recreating valid work.

After acceptance, copy the finished WebP assets to the requested output destination; if none was given, use descriptive, non-overwriting filenames in the project root. Keep the canonical base, manifest, and selected generation results for later actions; remove only expendable intermediates from this run. Retain incomplete runs for recovery.

Report the run and canonical-base paths, generated action IDs, delivered WebP links, contact-sheet and validation links, use of `$image-creator` for base/actions, and repairs, omissions, or visual-review limitations.