creating-plugins

creating-plugins is a skill for Claude Code from jaktestowac/awesome-copilot-for-testers. It costs 74 tokens per session (3,064 once invoked), scanned A, original, MIT.

A guide for packaging repository skills as installable GitHub Copilot plugins. It covers the plugin manifest, marketplace registration, generated skill copies, and checks that the copies match their source.

In plain words
What is it for?
Creating a plugin, grouping skills for installation, registering it in a marketplace, updating plugin descriptions or keywords, and fixing sync errors reported by the project checks.
Why use it?
It prevents plugin files from drifting away from the original skills and makes related skills easier to distribute as one installable unit. It also explains the project’s materialising and validation process.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

Install

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.

agentmods
npx agentmods add skills/jaktestowac/awesome-copilot-for-testers/creating-plugins
Any agent
npx skills add jaktestowac/awesome-copilot-for-testers --skill creating-plugins
Clone the repo
git clone --depth 1 https://github.com/jaktestowac/awesome-copilot-for-testers

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 creating-plugins

README.md
[![agentmods](https://agentmods.dev/badge/skills/jaktestowac/awesome-copilot-for-testers/creating-plugins.svg)](https://agentmods.dev/skills/jaktestowac/awesome-copilot-for-testers/creating-plugins)
Your own site
<a href="https://agentmods.dev/skills/jaktestowac/awesome-copilot-for-testers/creating-plugins"><img src="https://agentmods.dev/badge/skills/jaktestowac/awesome-copilot-for-testers/creating-plugins.svg" alt="Measured on agentmods" height="20"></a>
Per session 74 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,064 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00074 $0.03064
Opus 5 $0.00037 $0.01532
Sonnet 5 $0.00015 $0.00613
Haiku 4.5 $0.00007 $0.00306

Measured 6d ago against content hash 09e31171ad4d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

creating-plugins 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 6d 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.

plugins/creating-plugins/skills/creating-plugins/SKILL.md · 237 lines

How it starts

The opening of the file, as written. The whole thing — 237 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Creating Plugins

Use this skill when a skill or a small group of skills should be installable as a unit rather than copied by hand.

The rule that governs everything here: skills/ at the repository root is the source of truth, and everything under plugins/*/skills/ is generated output that happens to be committed. The generator is npm run plugin:materialize; the guard is scripts/check-plugin-sync.js, which CI runs as part of npm run lint. Editing a plugin copy directly produces a drift error and loses the edit on the next materialize.

When to Use

  • a skill is mature enough to install rather than copy
  • several related skills should ship together
  • a new plugin needs registering in the marketplace
  • npm run lint reports a plugin copy that does not match its source skill
  • a plugin's description or keywords need updating

Operating Principles

  • The root skill is the source of truth. Every change starts in skills/<name>/ and flows outward.
  • Plugin skill copies are generated. Never hand-edited, always regenerated.
  • A plugin is self-contained. The plugin format resolves skill paths relative to the plugin root, so a plugin cannot reference skills/ at the repository root. That is why the copies exist.
  • The marketplace entry comes first. The scaffolder builds the plugin directory from it, and rewrites the generated fields from it on every run - edits flow downstream, never back up.
  • A bundle is justified by use together. Two skills in one plugin because a user reaching for one reaches for the other, not because they share a topic.
  • The description is the install decision. It is what a user reads in a marketplace listing, and it is the only thing they read.

Workflow

Phase 0: Decide the bundle

A plugin ships one skill, or a small group used together.

Shape Justified when
One skill It stands alone, and nothing else is needed to use it
A skill plus its quick variant The pair covers routine and deep use of the same capability, like writing-unit-tests
Several cooperating skills A user reaching for one reliably reaches for the others in the same session

Read the full file on GitHub · 237 lines

Files

What ships with it

3 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.

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. 6d ago First seen · 237 lines · 74 tokens per session scan A 09e31171ad4d

Subscribe to this mod's changes

creating-plugins is a skill published in the GitHub repository jaktestowac/awesome-copilot-for-testers (113 stars, last pushed 10d ago), licensed MIT. It adds 74 tokens to every session and 3,064 once invoked, about $0.0004 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.