amethyst: Skill for Claude Code

.claude/skills/compose-slot-api-pattern/SKILL.md

compose-slot-api-pattern is a skill for Claude Code from vitorpamplona/amethyst. It costs 48 tokens per session (2,919 once invoked), scanned A, original, MIT.

A design pattern for reusable Jetpack Compose UI components, where the caller supplies changing visual sections while the component controls their layout.

In plain words
What is it for?
Use it to design or review reusable Compose components with variable content regions, such as list items with different leading, headline, supporting, or trailing content.
Why use it?
It prevents components from growing long lists of special-purpose text, icon, and boolean options whenever a new use case appears.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is vitorpamplona/amethyst's own configuration. It tells Claude Code how to work on amethyst itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything amethyst configures →

About the project

Amethyst is an Android client for Nostr, a social network protocol that lets people control their own social activity and connections. People use it to read and publish Nostr content, follow accounts, and exchange encrypted direct messages from Android and other supported platforms. The catalogue add-ons support workflows for developing or operating the client.

vitorpamplona/amethyst · 1,595 stars · on GitHub · amethyst.social

Reuse

Borrowing it

Nothing to install: this file belongs to vitorpamplona/amethyst. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/vitorpamplona/amethyst/main/.claude/skills/compose-slot-api-pattern/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/vitorpamplona/amethyst

Made for: Claude Code.

Wrote 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.

agentmods badge for compose-slot-api-pattern

README.md
[![agentmods](https://agentmods.dev/badge/skills/vitorpamplona/amethyst/compose-slot-api-pattern.svg)](https://agentmods.dev/skills/vitorpamplona/amethyst/compose-slot-api-pattern)
Your own site
<a href="https://agentmods.dev/skills/vitorpamplona/amethyst/compose-slot-api-pattern"><img src="https://agentmods.dev/badge/skills/vitorpamplona/amethyst/compose-slot-api-pattern.svg" alt="Measured on agentmods" height="20"></a>
Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,919 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00048 $0.02919
Opus 5 $0.00024 $0.01460
Sonnet 5 $0.00010 $0.00584
Haiku 4.5 $0.00005 $0.00292

Measured 7d ago against content hash b46c86968dc8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

compose-slot-api-pattern 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 7d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

.claude/skills/compose-slot-api-pattern/SKILL.md · 199 lines

How it starts

The opening of the file, as written. The whole thing — 199 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Compose: slot API pattern

Core principle

A reusable Compose component's job is to lay things out, not to enumerate what it lays out. The moment you write title: String, subtitle: String?, leadingIcon: ImageVector?, trailingIcon: ImageVector?, trailingText: String?, showSwitch: Boolean, switchValue: Boolean, onSwitchChange: (Boolean) -> Unit?, badge: String?, …, the component has stopped describing a layout and started enumerating call sites — and the next call site will need a parameter the component doesn't have.

The fix is to delegate content to the caller via @Composable lambda parameters. The component contributes structure (where the leading bit, headline, supporting bit, trailing bit go). The caller contributes everything that goes in those slots.

Material 3's ListItem is the canonical example: every visual piece is a slot (headlineContent, supportingContent, leadingContent, trailingContent, overlineContent), not a primitive. That's not over-engineering — it's the design that scales to every list-item shape the design system needs without ever editing ListItem again.

When to use this skill

You're designing or reviewing a Compose component intended for reuse (more than one call site, now or planned), its visual content varies by caller, and any of these is true:

  • Its signature has title: String, icon: ImageVector, actionText: String?, etc. — primitive types describing content.
  • It has multiple optional-content parameters that vary by call site (subtitle: String?, leadingIcon: ImageVector?, trailingText: String?).
  • It has boolean flags whose only purpose is to switch between content shapes (showChevron: Boolean, showSwitch: Boolean, mode: Mode.Text | Mode.Switch | …).
  • It accepts a String parameter where one caller would want a Text with custom style, a second caller a Text with a Badge, a third caller a row of icons.
  • It already has one slot (often trailing or content) and the rest of the parameters are still primitives.

Read the full file on GitHub · 199 lines

Changes

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.

  1. 7d ago First seen · 199 lines · 48 tokens per session scan A b46c86968dc8

Subscribe to this mod's changes

compose-slot-api-pattern is a skill published in the GitHub repository vitorpamplona/amethyst (1,595 stars, last pushed yesterday), licensed MIT. It adds 48 tokens to every session and 2,919 once invoked, about $0.0002 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 2026-08-30.

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