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 kylehughes/the-unofficial-swift-concurrency-migration-skill --skill migrating-to-swift-concurrencygit 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/skills/kylehughes/the-unofficial-swift-concurrency-migration-skill/migrating-to-swift-concurrency)<a href="https://agentmods.dev/skills/kylehughes/the-unofficial-swift-concurrency-migration-skill/migrating-to-swift-concurrency"><img src="https://agentmods.dev/badge/skills/kylehughes/the-unofficial-swift-concurrency-migration-skill/migrating-to-swift-concurrency/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/kylehughes/the-unofficial-swift-concurrency-migration-skill/migrating-to-swift-concurrency"><img src="https://agentmods.dev/badge/skills/kylehughes/the-unofficial-swift-concurrency-migration-skill/migrating-to-swift-concurrency.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 | $0.00048 | $0.00752 |
| Opus 5 | $0.00024 | $0.00376 |
| Sonnet 5 | $0.00010 | $0.00150 |
| Haiku 4.5 | $0.00005 | $0.00075 |
Grade A, and why
migrating-to-swift-concurrency 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 12d 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 — 50 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Swift Concurrency Migration Guide
The complete content of the Swift Concurrency Migration Guide by Apple. This guide helps you migrate your code to take advantage of Swift's data-race safety guarantees and the Swift 6 language mode.
Documentation
- Data Race Safety (Guide/DataRaceSafety.md): Learn about the fundamental concepts Swift uses to enable data-race-free
- Migration Strategy (Guide/MigrationStrategy.md): Get started migrating your project to the Swift 6 language mode.
- Enable data-race safety checking (Guide/EnableDataRaceSafety.md): Use Swift 6 to get full data-race safety checking or add checking to an existing Swift 5 project.
- Common Compiler Errors (Guide/CommonProblems.md): Identify, understand, and address common problems you can encounter while
- Incremental Adoption (Guide/IncrementalAdoption.md): Learn how you can introduce Swift concurrency features into your project
- Migrating to upcoming language features (Guide/FeatureMigration.md): Migrate your project to upcoming language features.
- Source Compatibility (Guide/SourceCompatibility.md): See an overview of potential source compatibility issues.
- Library Evolution (Guide/LibraryEvolution.md): Annotate library APIs for concurrency while preserving source and ABI
- Runtime Behavior (Guide/RuntimeBehavior.md): Learn how Swift concurrency runtime semantics differ from other runtimes you may
Code Examples
Swift source files demonstrating migration patterns and concurrency concepts:
- Boundaries.swift (Examples/Boundaries.swift): Example code demonstrating Boundaries.
- ConformanceMismatches.swift (Examples/ConformanceMismatches.swift): Example code demonstrating ConformanceMismatches.
- DispatchQueue_PendingWork.swift (Examples/DispatchQueue_PendingWork.swift): Example code demonstrating DispatchQueue PendingWork.
- Globals.swift (Examples/Globals.swift): Example code demonstrating Globals.
- IncrementalMigration.swift (Examples/IncrementalMigration.swift): Example code demonstrating IncrementalMigration.
- PreconcurrencyImport.swift (Examples/PreconcurrencyImport.swift): Example code demonstrating PreconcurrencyImport.
- main.swift (Examples/main.swift): Example code demonstrating main.
What ships with it
17 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.
- Examples/Boundaries.swift 5.2 KB
- Examples/ConformanceMismatches.swift 4.3 KB
- Examples/DispatchQueue_PendingWork.swift 402 B
- Examples/Globals.swift 2.2 KB
- Examples/IncrementalMigration.swift 1.0 KB
- Examples/main.swift 384 B
- Examples/PreconcurrencyImport.swift 326 B
- Guide/CommonProblems.md 26 KB
- Guide/DataRaceSafety.md 22 KB
- Guide/EnableDataRaceSafety.md 5.9 KB
- Guide/FeatureMigration.md 3.2 KB
- Guide/IncrementalAdoption.md 17 KB
- Guide/LibraryEvolution.md 7.6 KB
- Guide/MigrationStrategy.md 4.3 KB
- Guide/RuntimeBehavior.md 2.6 KB
- Guide/SourceCompatibility.md 4.8 KB
- LICENSE.txt 11 KB
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.
- 12d ago First seen · 50 lines · 48 tokens per session scan A 3c6327b09569
migrating-to-swift-concurrency is a skill published in the GitHub repository kylehughes/the-unofficial-swift-concurrency-migration-skill (56 stars, last pushed 9mo ago), licensed MIT. It adds 48 tokens to every session and 752 once invoked, about $0.0002 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.
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