Swift Concurrency Skill: analyze project concurrency first, then talk about a Swift 6 migration

Who it is for

If you maintain a Swift project and want a coding assistant to talk about safe concurrency, performance, and a Swift 6+ migration from one expert skill—instead of mixing old thread APIs from memory—this skill is a better fit. It targets any AI coding tool that supports the Agent Skills open format. The format notes are at

https://agentskills.io/home

You already need a Swift project that can be analyzed, and you must accept adding the swift-concurrency skill with one npx command. If you only want to read WWDC notes and do not plan to let the assistant read the repository, the benefit is limited. The page names several products that show a client roster, and it also writes "any tool that supports this format", so do not treat the examples as a closed roster.

First try in 3 minutes

The official install is this one line:

npx skills add https://github.com/avdlee/swift-concurrency-agent-skill --skill swift-concurrency

It writes the skill into the current Agent environment. Confirm you have npx locally and that this is the environment of the Swift project you want to analyze, then run it. Do not put another installer beside it.

After install, do the official example as a read-only analysis; do not migrate yet:

Use the swift concurrency skill and analyze the current project for Swift Concurrency improvements

The success signal follows the page's How to verify: the assistant should cite the triage/playbook in skills/swift-concurrency/SKILL.md and jump into the reference file that matches your error or task. If it only gives generic async advice and never mentions this playbook, stop and have it open the skill file. During analysis, do not let it change actors, change isolation, or raise the project to Swift 6.

Usage examples

Example 1: Check the current project for concurrency improvements. Use the official prompt in the previous section. The task is analysis, not code edits. The available page text does not say which directories it scans, and it does not say the report format. So what you can confirm is: it states that it used the swift concurrency skill, and it lands on the triage playbook in SKILL.md. If the advice has already become "I will edit these files for you", ask for a file roster first, then decide.

Example 2: Look up a reference page against a concrete error or migration task. The verify step says: for your error or task, jump into the matching reference file. When you already have a compiler concurrency diagnostic, or you clearly want a Swift 6+ migration, have the assistant open the playbook first, then the matching reference, instead of changing the language mode right away. Performance work is also listed as a capability, but there is no performance-probe command. So a performance task also starts by checking the reference file; if the command is missing, do not invent a benchmark script.

Limits

This is an expert-guidance skill, not an automatic migrator. Safe concurrency, performance, and Swift 6+ migration are in scope, but the first stop should be analysis and citation. The repository is also written as a portable Agent Plugin (spec 1.0.0); compatible clients discover the skill from the root plugin.json and skills/. That is packaging, not a second install command. Install still uses only the npx skills add above.

The plugin spec is at

https://agent-plugins.org/

Do not take that as a reason to use an unwritten store install. A complete roster of reference files does not appear in the available page text; you cannot name a specific reference from this material.

The first stop is analysis. Any edit to Swift concurrency code, any language-mode change, or any bulk add of @MainActor must first have the assistant name the files it will change and the reference page it relies on; you confirm, then it continues.