# Liquid Glass Motion

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- **Type:** Skill
- **Install:** `agentstack add skill-yordilorenzo-liquid-glass-skills-liquid-glass-motion`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [YordiLorenzo](https://agentstack.voostack.com/s/yordilorenzo)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [YordiLorenzo](https://github.com/YordiLorenzo)
- **Source:** https://github.com/YordiLorenzo/liquid-glass-skills/tree/main/liquid-glass-motion

## Install

```sh
agentstack add skill-yordilorenzo-liquid-glass-skills-liquid-glass-motion
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Liquid Glass — motion, animation, and shaders

Companion to the **liquid-glass** skill (`~/.claude/skills/liquid-glass/`). Same tag system:
`[verified]` / `[apple]` / `[multi]` / `[single]` / `[version-pinned]` — see that skill's
SKILL.md. Composed 2026-08 and verified against Apple documentation and SDK interfaces.

## Operating rules

1. Before generating code, ALWAYS read the availability firewall in the companion
   **liquid-glass** skill (installed alongside this one):
   `references/availability-and-sdk27.md`. Motion code trips the same SDK-27 breakages
   (`.if` ban, `@ContentBuilder`, renames).
2. Load references on demand via the router — one topic, one file.
3. The motion model: Liquid Glass and its motion were designed together. Glass does not
   fade — it materializes by modulating lensing; when glass grows, its material gets
   thicker (deeper shadow, stronger lensing). Size change is a material change, which is
   why morphs must be the system animation, never hand-faked.
4. Verify motion claims against `references/` before repeating them — circulating write-ups
   get several of these facts wrong; the corrected facts live in these files.
5. Profiling evidence beats reasoning: record an Instruments trace with `xctrace` before
   optimizing, and never trust the iOS Simulator for the SwiftUI instrument — see
   `references/performance-and-instrumentation.md`.

## Hard rules (the short list)

1. Never animate glass with `.opacity` / fades — use `glassEffectTransition`
   (`.materialize` is the sanctioned fade-like option). [multi]
2. Morphing silently no-ops unless ALL four hold: same `GlassEffectContainer`;
   `glassEffectID` per element in one shared `@Namespace`; the change is view
   insertion/removal (not a value change); the state change is inside `withAnimation`.
   Plus geometry: nearest edges within the container's `spacing`. [multi]
3. The interactive "squish" is one boolean — `.interactive()`. No public spring/damping/
   stiffness knobs exist; do not promise tunable jelly. [multi]
4. Gate every glass animation on `accessibilityReduceMotion` — the default morph is a
   kinetic effect, and reduce-motion users have experienced it as flickering. The system
   does NOT gate your `withAnimation` for you. [multi]
5. One animation source per property — never mix implicit `.animation`, `withAnimation`,
   and scroll-driven updates on the same property. Implicit later in the view tree silently
   wins over explicit. [multi]
6. The animation context must live OUTSIDE a conditional — an `.animation()` inside the
   `if` is destroyed with the view and removal never animates. [multi]
7. Prefer renderer-side motion for scroll: `scrollTransition` / `visualEffect(in:)` over
   observable scroll-offset plumbing. [apple]
8. Animate transforms first (scale/offset/rotation), frames second, identity changes last.
   [multi]

## Topic router

| Topic | Reference |
|---|---|
| Springs, curves, precedence, Transaction, @Animatable, CA bridge | `references/animation-fundamentals.md` |
| Glass morphing, glassEffectID, union, glassEffectTransition | `references/morphing.md` |
| Navigation zoom, custom Transition, sheets, touch-vs-trackpad | `references/transitions-and-navigation.md` |
| Scroll-driven motion, scrollTransition, visualEffect, chrome interplay | `references/scroll-driven.md` |
| PhaseAnimator, KeyframeAnimator, symbol effects | `references/phase-and-keyframe.md` |
| Reduce Motion gating, replacement tables | `references/reduce-motion.md` |
| Metal shaders with/under/instead-of glass | `references/metal-and-glass.md` |
| Performance model, xctrace profiling | `references/performance-and-instrumentation.md` |
| Static glass, availability, toolbars, platform APIs, a11y of the material | liquid-glass skill |
| Choosing the actual spring/damping/duration values | apple-motion-feel skill |

## Scripts

`scripts/record_trace.py` and `scripts/analyze_trace.py` (+ `instruments_parser/`) — vendored
from Antoine van der Lee's SwiftUI-Agent-Skill (MIT; licence ships beside them as
`scripts/LICENSE-AvdLee-SwiftUI-Agent-Skill`). Record and parse Instruments traces (Time
Profiler, Hangs, Animation Hitches, SwiftUI lanes) into JSON/markdown. Usage and interpretation:
`references/performance-and-instrumentation.md`.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [YordiLorenzo](https://github.com/YordiLorenzo)
- **Source:** [YordiLorenzo/liquid-glass-skills](https://github.com/YordiLorenzo/liquid-glass-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-yordilorenzo-liquid-glass-skills-liquid-glass-motion
- Seller: https://agentstack.voostack.com/s/yordilorenzo
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.