Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/rube-de/cc-skillsnpx agentmods add skills/rube-de/cc-skills/plugin-devWrote 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/rube-de/cc-skills/plugin-dev)<a href="https://agentmods.dev/skills/rube-de/cc-skills/plugin-dev"><img src="https://agentmods.dev/badge/skills/rube-de/cc-skills/plugin-dev/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/rube-de/cc-skills/plugin-dev"><img src="https://agentmods.dev/badge/skills/rube-de/cc-skills/plugin-dev.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00049 | $0.00581 |
| Opus 5.5 | $0.00020 | $0.00232 |
| Sonnet 5.5 | $0.00010 | $0.00116 |
| Haiku 4.5 | $0.00005 | $0.00058 |
Grade A, and why
plugin-dev 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 — 68 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Plugin Development Tools
On-demand validation and hook auditing for the cc-skills marketplace.
Triggers
Use this skill when the user says: "validate plugins", "check plugin", "hook audit", "validate skills", "audit hooks", "check skill frontmatter", "plugin validation".
Available Tools
1. Plugin Validation
Validates all registered plugins: JSON Schema, source paths, orphan detection, SKILL.md frontmatter, plugin.json version pins, and agent frontmatter.
bun scripts/validate-plugins.mjs
What it checks:
- marketplace.json conforms to JSON Schema
- All plugin
sourcepaths exist on disk - No orphaned plugin directories (dirs without marketplace entries)
- SKILL.md frontmatter has valid
name(kebab-case) and non-emptydescription - Every plugin has at least one component directory (skills/, hooks/, commands/, agents/)
- No
.claude-plugin/plugin.jsonpins aversion - Every agent file under
agents/(subfolders included) has frontmatter that parses as YAML and declares none ofhooks,mcpServers,permissionMode,initialPrompt— Claude Code ignores those for plugin agents, and drops every field of an agent whose frontmatter doesn't parse
2. Hook Audit
Scans hook and script files for silent failure patterns.
bash plugins/plugin-dev/scripts/audit-hooks.sh
What it checks:
- Shell scripts (
.sh):mkdir/cp/mv/rmwithout error handling (unlessset -eis active) - Python scripts (
.py): bareexcept: passorexcept Exception: pass - Optional: ShellCheck integration (skipped with message if not installed)
Exit codes: 0 = clean, 1 = findings
Workflow
When the user asks to validate or audit:
- Run
bun scripts/validate-plugins.mjsfor plugin validation - Run
bash plugins/plugin-dev/scripts/audit-hooks.shfor hook auditing - Report results clearly — separate passing checks from failures
- For failures, suggest specific fixes
Scaffolding
To scaffold a new plugin interactively, use the command:
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 Changed · +2 lines f8dc28ac7427
- 1mo ago First seen · 66 lines · 49 tokens per session scan A d84e2a0d34f8
plugin-dev is a skill published in the GitHub repository rube-de/cc-skills (10 stars, last pushed 5d ago), licensed MIT. It adds 49 tokens to every session and 581 once invoked, about $0.0002 per session on Opus 5.5. 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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