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.
/plugin marketplace add Londeren/claude-pluginsnpx agentmods add plugins/londeren/claude-plugins/prompt-writergit clone --depth 1 https://github.com/Londeren/claude-pluginsWrote 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/plugins/londeren/claude-plugins/prompt-writer)<a href="https://agentmods.dev/plugins/londeren/claude-plugins/prompt-writer"><img src="https://agentmods.dev/badge/plugins/londeren/claude-plugins/prompt-writer.svg" alt="Measured on agentmods" height="20"></a>Grade A, and why
prompt-writer 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 3d 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.
What it actually says
{
"name": "prompt-writer",
"displayName": "Prompt Writer",
"version": "1.0.1",
"description": "Methodology for writing LLM prompts, derived from analysis of Claude system prompts (Opus 4.7, Fable 5, Opus 5) and attention mechanics. Routes a request into one of five prompt types and applies the matching template, then audits the draft against a self-check list.",
"author": {
"name": "Sergey Lebedev",
"url": "https://github.com/Londeren"
},
"homepage": "https://github.com/Londeren/claude-plugins",
"repository": "https://github.com/Londeren/claude-plugins",
"license": "MIT",
"keywords": [
"prompt-engineering",
"system-prompt",
"prompt-writing",
"llm",
"agent-prompt",
"multilingual"
]
}
What it installs
The manifest is a name and a version. 1 skill travel with it, and installing the plugin installs all of them — 208 tokens a session between them. Each is measured on its own page, and each can be installed alone.
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.
- 3d ago First seen · 22 lines scan A f8402cfedc17
prompt-writer is a plugin published in the GitHub repository Londeren/claude-plugins (4 stars, last pushed 9d ago), licensed MIT. Its token cost is not measured: this kind of file is read by the harness, not the model. 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 plugins, from other repositories
humanizer
Rewrite AI-sounding text so it reads naturally without changing what it says.
nextjs
Official Next.js skills: adopt and optimize Cache Components, adopt Partial Prefetching, and verify runtime behavior against a running dev server.
claude-plugins-official marketplace
Directory of popular Claude Code extensions including development tools, productivity plugins, and MCP integrations.
knowledge-work-plugins marketplace
Plugin marketplace listing 98 plugins: noibu, productivity, enterprise-search, cowork-plugin-management, sales.
ecc
Harness-native ECC plugin for engineering teams - 68 agents, 286 skills, 94 legacy command shims, reusable hooks, rules, MCP conventions, and operator workflows for Claude Code plus adjacent agent harnesses.
ui-ux-pro-max
UI/UX design intelligence. Searchable local database with 84 styles, 192 palettes, 74 font pairings, 25 charts, and 22 stacks (React, Next.js, Vue, Nuxt.js, Nuxt UI, Svelte, Astro, SwiftUI, React Native, Flutter, Tailwind, shadcn/ui, Jetpack Compose, Angular, Laravel, JavaFX, WPF, WinUI, Avalonia, Uno Platform, UWP…