Borrowing it
Nothing to install: this file belongs to kylehughes/the-unofficial-swift-concurrency-migration-skill. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/kylehughes/the-unofficial-swift-concurrency-migration-skill/main/CLAUDE.mdgit clone --depth 1 https://github.com/kylehughes/the-unofficial-swift-concurrency-migration-skillWrote 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/instructions/kylehughes/the-unofficial-swift-concurrency-migration-skill/claude-md)<a href="https://agentmods.dev/instructions/kylehughes/the-unofficial-swift-concurrency-migration-skill/claude-md"><img src="https://agentmods.dev/badge/instructions/kylehughes/the-unofficial-swift-concurrency-migration-skill/claude-md/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/instructions/kylehughes/the-unofficial-swift-concurrency-migration-skill/claude-md"><img src="https://agentmods.dev/badge/instructions/kylehughes/the-unofficial-swift-concurrency-migration-skill/claude-md.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 | $0.01031 | $0.01031 |
| Opus 5 | $0.00515 | $0.00515 |
| Sonnet 5 | $0.00206 | $0.00206 |
| Haiku 4.5 | $0.00103 | $0.00103 |
Grade A, and why
the-unofficial-swift-concurrency-migration-skill CLAUDE.md 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 13d 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 — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to programming agents, like Claude Code (claude.ai/code), when working with code in this repository.
Repository Purpose
This repository packages the Swift Concurrency Migration Guide from Apple into a Claude Skill format. The skill is automatically generated from the official Swift migration guide repository. This repository is exposed as a Claude plugin marketplace which vends a plugin which contains the skill.
Build Commands
Generate the Skill Package
python3 package.py
This command:
- Clones the official Swift migration guide repository (https://github.com/swiftlang/swift-migration-guide.git)
- Extracts and organizes the documentation content
- Copies Swift example files from Sources/Examples
- Generates the
migrating-to-swift-concurrencydirectory with the skill content - Creates
migrating-to-swift-concurrency.ziparchive for distribution
Build Options
--output DIRor-o DIR: Specify custom output directory (default:./migrating-to-swift-concurrency)--keep-temp: Keep the temporary git clone after packaging--dry-run: Simulate operations without writing files
Code Architecture
Design Philosophy: Separation of Concerns
The repository manages two distinct responsibilities which are intentionally decoupled:
-
Skill Generation (
package.py):- Goal: To be a standalone, portable tool that transforms the Swift migration guide into a canonical Claude Skill format.
- Constraint: It must have zero dependencies and be runnable by anyone, anywhere, to generate the skill.
- Scope: It strictly handles content extraction and generation. It generally does not know about the release process, versioning schemes, or marketplace metadata.
-
Distribution & Lifecycle (Repository & Workflow):
- Goal: To vend the generated skill via releases and the Claude Marketplace.
- Scope: This layer (handled by
.github/workflows/release.yml) manages the "outer loop": running the generator, detecting changes, managingmarketplace.json, and creating Git tags/releases.
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.
- 13d ago First seen · 94 lines · 1,031 tokens per session scan A 9a0cec314456
the-unofficial-swift-concurrency-migration-skill CLAUDE.md is an instructions file published in the GitHub repository kylehughes/the-unofficial-swift-concurrency-migration-skill (56 stars, last pushed 9mo ago), licensed MIT. It adds 1,031 tokens to every session, about $0.0052 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.
Other instructions, from other repositories
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).