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 lttr/claude-marketplace --skill plugin-creatorgit clone --depth 1 https://github.com/lttr/claude-marketplaceWrote 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/lttr/claude-marketplace/plugin-creator)<a href="https://agentmods.dev/skills/lttr/claude-marketplace/plugin-creator"><img src="https://agentmods.dev/badge/skills/lttr/claude-marketplace/plugin-creator.svg" alt="Measured on agentmods" 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 | $0.00064 | $0.01513 |
| Opus 5 | $0.00032 | $0.00757 |
| Sonnet 5 | $0.00013 | $0.00303 |
| Haiku 4.5 | $0.00006 | $0.00151 |
Grade A, and why
plugin-creator 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.
How it starts
The opening of the file, as written. The whole thing — 248 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Plugin Creator
Official docs: https://code.claude.com/docs/en/plugins.md, https://code.claude.com/docs/en/plugins-reference.md, https://code.claude.com/docs/en/plugin-marketplaces.md. Fetch when unsure about manifest schema, distribution, or recent features.
Overview
Create and manage Claude Code plugins with proper structure, manifests, and marketplace integration. This skill provides workflows, automation scripts, and reference documentation for plugin development.
When to Use This Skill
Trigger this skill when:
- Creating new plugins for a marketplace
- Adding or modifying plugin components (commands, skills, agents, hooks)
- Updating plugin versions
- Working with plugin or marketplace manifests
- Setting up local plugin testing
- Publishing plugins to marketplaces
Quick Start
Creating a New Plugin
Use the create_plugin.py script to generate plugin structure:
python scripts/create_plugin.py plugin-name \
--marketplace-root /path/to/marketplace \
--author-name "Your Name" \
--author-email "[email protected]" \
--description "Plugin description" \
--keywords "keyword1,keyword2" \
--category "productivity"
This automatically:
- Creates plugin directory structure
- Generates
plugin.jsonmanifest - Creates README template
- Updates
marketplace.json
Bumping Plugin Version
Use bump_version.py to update versions in both manifests:
python scripts/bump_version.py plugin-name major|minor|patch \
--marketplace-root /path/to/marketplace
Semantic versioning rules:
- major: Breaking changes (1.0.0 → 2.0.0)
- minor: New features, refactoring (1.0.0 → 1.1.0)
- patch: Bug fixes, docs only (1.0.0 → 1.0.1)
Plugin Development Workflow
1. Create Plugin Structure
Manual approach if not using create_plugin.py:
mkdir -p plugins/plugin-name/.claude-plugin
mkdir -p plugins/plugin-name/commands
mkdir -p plugins/plugin-name/skills
2. Create Plugin Manifest
What ships with it
5 files 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.
- 7d ago First seen · 248 lines · 64 tokens per session scan A ceb3ff0d603f
plugin-creator is a skill published in the GitHub repository lttr/claude-marketplace (2 stars, last pushed 5d ago), licensed MIT. It adds 64 tokens to every session and 1,513 once invoked, about $0.0003 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.
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