iOS Development

What it does

When your agent uses it

• ANY iOS-related task: writing Swift/SwiftUI/UIKit code
• Architecting apps
• Debugging crashes
• Setting up navigation

Example prompts

• “/ios-development”

Workflow steps

5 steps, taken from the first numbered list in SKILL.md.

1. 1UI framework → SwiftUI / UIKit / mixed?
2. 2Architecture → MVVM / TCA / VIPER / Clean / MVC?
3. 3iOS target → iOS 16 / 17 / 18? (affects API availability)
4. 4Task type → new feature / debug / refactor / architecture / performance / release?
5. 5Graphics intensity → стандартный UI / средняя 3D / тяжёлая графика / Metal?

What it can do on your machine

Read from SKILL.md and the folder at commit c1126ce. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are swift).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

iOS Development loads about 2.2k tokens when it runs, and up to ~27k if it reads all its reference files. Until then it costs about 208 tokens; SKILL.md has 595 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~208

When it runs · the whole SKILL.md, loaded when a task matches

~2.2k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~27k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from AnastasiyaW/codex-claude-code-config at commit c1126ce, republished under its MIT licence (© AnastasiyaW). 595 words, ~2,240 tokens.

name

ios-development

description

Comprehensive iOS app development skill. Use this skill for ANY iOS-related task: writing Swift/SwiftUI/UIKit code, architecting apps, debugging crashes, setting up navigation, networking, data persistence, animations, performance optimization, App Store submission, Xcode configuration. Trigger when user mentions: iOS, Swift, SwiftUI, UIKit, Xcode, iPhone/iPad app, Combine, CoreData, SwiftData, MVVM, TCA, URLSession, async/await, @State/@Binding/@ObservableObject, NavigationStack, XCTest, TestFlight, provisioning profiles, or any Apple platform development. Always use this skill before writing iOS code or architecture. Do NOT use for web frontends (HTML/CSS/JS, React/Vue, browser UI) — even a WebView's page content is web work; use frontend-design for that. This skill is native Apple-platform code only.

if #available(iOS 17, *) {
    // SwiftData or @Observable
} else {
    // fallback
}

// Prefer this
func loadUser() async throws -> User {
    let data = try await URLSession.shared.data(from: url).0
    return try JSONDecoder().decode(User.self, from: data)
}

// Call site
Task {
    do {
        user = try await loadUser()
    } catch {
        errorMessage = error.localizedDescription
    }
}

enum AppError: LocalizedError {
    case networkUnavailable
    case decodingFailed(String)
    case unauthorized
    
    var errorDescription: String? {
        switch self {
        case .networkUnavailable: return "No internet connection"
        case .decodingFailed(let detail): return "Data error: \(detail)"
        case .unauthorized: return "Please sign in again"
        }
    }
}

Is the screen purely data-display with simple interaction?
  YES → MVC / simple SwiftUI View with @State is fine
  NO ↓

Is business logic testable without UI?
  Required → use ViewModel (MVVM) or Store (TCA)

Is navigation/routing complex (deep links, coordinator)?
  YES → read references/navigation.md → Coordinator pattern

Is the team large or is this a long-lived product?
  YES → Clean Architecture or TCA → read references/architecture.md

Default for most apps: MVVM + Coordinator

Local transient state       → @State
Passed from parent          → @Binding
Shared across views         → @StateObject / @ObservedObject (iOS 16-)
                            → @State with @Observable class (iOS 17+)
App-wide environment        → @EnvironmentObject / @Environment

@Observable
class UserStore {
    var users: [User] = []
    var isLoading = false
}

// In View — no property wrapper needed
struct UserListView: View {
    var store: UserStore  // just pass it
    var body: some View {
        List(store.users) { Text($0.name) }
    }
}

class UserViewModel: ObservableObject {
    @Published var users: [User] = []
    @Published var isLoading = false
}

struct UserListView: View {
    @StateObject private var vm = UserViewModel()
}

// Unit test — ViewModel
@MainActor
final class UserViewModelTests: XCTestCase {
    func testLoadUsers() async throws {
        let vm = UserViewModel(service: MockUserService())
        await vm.loadUsers()
        XCTAssertFalse(vm.users.isEmpty)
    }
}

// UI test — basic
func testLoginFlow() {
    let app = XCUIApplication()
    app.launch()
    app.textFields["Email"].tap()
    app.textFields["Email"].typeText("test@example.com")
    app.buttons["Continue"].tap()
    XCTAssertTrue(app.navigationBars["Home"].exists)
}

© AnastasiyaW, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 8 other files (references) in skills/ios/ios-development of AnastasiyaW/codex-claude-code-config.

• SKILL.md
• references/architecture.md
• references/data.md
• references/metal-graphics.md
• references/navigation.md
• references/networking.md
• references/performance.md
• references/swiftui.md
• references/uikit.md

Open the folder on GitHubat commit c1126ce