Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add SummerEngine/summer-engine-agent --skill sprite-sheetgit clone --depth 1 https://github.com/SummerEngine/summer-engine-agentWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/summerengine/summer-engine-agent/sprite-sheet)<a href="https://agentmods.dev/skills/summerengine/summer-engine-agent/sprite-sheet"><img src="https://agentmods.dev/badge/skills/summerengine/summer-engine-agent/sprite-sheet/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/summerengine/summer-engine-agent/sprite-sheet"><img src="https://agentmods.dev/badge/skills/summerengine/summer-engine-agent/sprite-sheet.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00077 | $0.03812 |
| Opus 5.5 | $0.00031 | $0.01525 |
| Sonnet 5.5 | $0.00015 | $0.00762 |
| Haiku 4.5 | $0.00008 | $0.00381 |
Grade A, and why
sprite-sheet scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 245 lines — stays where its author put it; the contents beside it link to each section on GitHub.
sprite-sheet — Frame-by-Frame 2D Animation
This skill produces a grid of animation frames for a 2D character — walk cycle, idle bob, attack swing, death sequence — and wires the result into an AnimatedSprite2D via a SpriteFrames resource.
Up-front honesty: sprite-sheet generation from a single text-to-image call is unreliable. Models can render "a sprite sheet of a knight walking" and produce 8 frames, but the inter-frame consistency (same anatomy, same costume, same lighting) is poor. Limbs morph between frames. Pixel sprites get extra fingers in frame 3. The result usually looks worse than the static sprite did.
This skill therefore offers three paths, ranked by reliability:
- Per-frame img2img (most reliable) — generate the base pose, then generate each subsequent frame via
referenceImageUrlwith a small pose delta. Composite the frames into a sheet externally or wire each as a separateSpriteFramesentry. - Single-call sheet + auto-slice (fast; sheet coherence is the gamble, not the cutting) — one prompt asks for the grid, then
summer_slice_asset_sheetcuts it into individual frame assets server-side. Worth trying once for short cycles (4 frames or fewer) before falling back to (1). - Manual authoring (most reliable, slowest) — hand-author in Aseprite or Piskel. For pixel art at 32×32, this is often faster than fixing AI generations.
There is no single "generate a sprite sheet" tool, but there is a shared two-tool sheet pipeline, and it is the same one Studio's Guided "sprite-sheet" workflow runs: summer_generate_image produces one sheet, then summer_slice_asset_sheet({ assetId }) runs the server-side vision slicer that removes the background, detects each frame's bounding box, crops, and uploads every frame as its own asset. Call summer_get_studio_workflow({ workflowId: "sprite-sheet" }) for the current ordered recipe and its stated limitations. Only Studio's frame-preview and visual timing-review UI is unreachable from MCP — the generation and the slicing both are reachable.
So do not tell the user to cut a generated sheet by hand or in ImageMagick. The cutting is automated; what is unreliable is inter-frame consistency inside the generated sheet.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2mo ago First seen · 245 lines · 77 tokens per session scan A 52f6047ae8e3
sprite-sheet is a skill published in the GitHub repository SummerEngine/summer-engine-agent (59 stars, last pushed 1mo ago), licensed MIT. It adds 77 tokens to every session and 3,812 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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