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.
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 vitorpamplona/amethyst --skill quartzgit clone --depth 1 https://github.com/vitorpamplona/amethystWrote 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/vitorpamplona/amethyst/quartz)<a href="https://agentmods.dev/skills/vitorpamplona/amethyst/quartz"><img src="https://agentmods.dev/badge/skills/vitorpamplona/amethyst/quartz/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/vitorpamplona/amethyst/quartz"><img src="https://agentmods.dev/badge/skills/vitorpamplona/amethyst/quartz.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 | $0.00000 | $0.01891 |
| Opus 5.5 | $0.00000 | $0.00756 |
| Sonnet 5.5 | $0.00000 | $0.00378 |
| Haiku 4.5 | $0.00000 | $0.00189 |
Grade A, and why
quartz 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 4d 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 — 135 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Quartz (Nostr for Kotlin Multiplatform)
Quartz is the protocol library behind the Amethyst Nostr client, published on Maven
Central as com.vitorpamplona.quartz. This skill is for projects that depend on it.
The full guides live in the repo:
- Client guide — transports, subscriptions, publishing, filters, connection lifecycle.
- Relay guide — running a relay on Quartz: event stores, policies, NIP-11 limits and documents.
- Client architecture — how to structure a feed-style app on top of it.
- One-shot relay operations —
the catalog of
fetch*,count, publish and negentropy helpers.
Setup
// commonMain, or a JVM/Android module. Take the latest version from Maven Central:
// https://central.sonatype.com/search?q=com.vitorpamplona.quartz
implementation("com.vitorpamplona.quartz:quartz:<version>")
Targets: Android, JVM, iosArm64, iosSimulatorArm64, macosArm64, linuxX64 (per-target
artifacts such as quartz-jvm and quartz-android exist for non-KMP builds). Ktor is not
a dependency: on JVM and Android, Quartz talks to relays through OkHttp and parses events
with Jackson.
Where things are
Packages are named after the NIP they implement: nip01Core (events, filters, relay
client, crypto, signers), nip19Bech32, nip05DnsIdentifiers, nip17Dm, nip44Encryption,
nip57Zaps, and so on, under com.vitorpamplona.quartz. To find a NIP, look for its
nipNN… package first; event classes expose const val KIND and a build(...) template.
Connect and read
NostrClient is transport-agnostic: it needs a WebsocketBuilder. On JVM and Android,
use the bundled OkHttp one (add com.squareup.okhttp3:okhttp to construct the client);
on other targets, implement the three small interfaces shown in the client guide.
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.
- 4d ago First seen · 135 lines · 0 tokens per session scan A 4ea0520c8d0c
quartz is a skill published in the GitHub repository vitorpamplona/amethyst (1,611 stars, last pushed yesterday), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,891 tokens. 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 2026-10-12.
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