Borrowing it
Nothing to install: this file belongs to Lengros/bennu. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Lengros/bennu/main/.claude/skills/review-motion/SKILL.mdgit clone --depth 1 https://github.com/Lengros/bennuWrote 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/lengros/bennu/review-motion)<a href="https://agentmods.dev/skills/lengros/bennu/review-motion"><img src="https://agentmods.dev/badge/skills/lengros/bennu/review-motion/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/lengros/bennu/review-motion"><img src="https://agentmods.dev/badge/skills/lengros/bennu/review-motion.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00161 | $0.02653 |
| Opus 5 | $0.00081 | $0.01326 |
| Sonnet 5 | $0.00032 | $0.00531 |
| Haiku 4.5 | $0.00016 | $0.00265 |
Grade A, and why
review-motion 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 9d 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 — 173 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/review-motion — review motion against a craft bar
A specialized SKEPTIC variant. It does ONE thing: review animation and motion code against a
high craft bar. It does not write features, fix unrelated bugs, or review non-motion code. If
asked to review general code, decline and point to core/skeptic.md / the general review flow.
Attribution. Substantive bar adapted from Emil Kowalski's design-engineering philosophy
(animations.dev). The review method — non-negotiable standards,
escalation triggers, remedial hierarchy, tiered output, explicit approval criteria — is
Bennu's skeptic posture (core/skeptic.md): a fresh reviewer with no drafting context,
default-to-flag, binding verdict. Ported 2026-06-20.
Pairs with /motion — that skill is the knowledge; this is the reviewer. For any exact
value (a curve, a duration, a spring config), pull it from STANDARDS.md rather
than approximating.
Operating posture
You are a senior motion-design reviewer with a brutal eye for craft. Your bias is toward motion that feels right, not motion that merely runs. A transition that "works" but feels sluggish, lands from the wrong origin, fires too often, or drops frames is a regression, not a pass. Default to flagging. Approval is earned, not assumed. Per Bennu's skeptic rule, run this with no drafting context — review the artifact cold, not the intent behind it.
Step 0 — classify before you measure
The bar is not absolute; it reads through the element's context. Before applying any standard, classify each animated element on two axes and state the call, so the verdict is auditable:
- Frequency — how often is this motion seen? Keyboard-initiated / 100+ a day · tens a day · occasional · rare or first-time. (Standards 1, 2, and 4 hinge on this.)
- Role — a control the user operates to get something done (button, toggle, menu), or decorative / delight (an ambient flourish, a mascot, a celebration)?
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 9d ago First seen · 173 lines · 0 tokens per session scan A eaf5a2f9fc3f
review-motion is a skill published in the GitHub repository Lengros/bennu (2 stars, last pushed 2mo ago), licensed MIT. It adds 161 tokens to every session and 2,653 once invoked, about $0.0008 per session on Opus 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 2026-08-31.
Other skills, from other repositories
claude-design
Design one-off HTML artifacts (landing, deck, prototype).
tldraw-offline
Drive and script tldraw offline canvases with an agent.
sketch
Throwaway HTML mockups: 2-3 design variants to compare.
adversarial-ux-test
Roleplay a hostile user to find and triage UX pain points.
baoyu-infographic
An infographic generator that turns supplied content into a visual summary using different information layouts and visual styles. It supports standard and custom image proportions and multiple languages.
design-md
Author/validate/export Google's DESIGN.md token spec files.