Design

Use when SwiftUI view debugging requires systematic investigation - view updates not working after basic troubleshooting, intermittent UI issues, complex state dependencies, or when Self._printChanges() shows unexpected update patterns - systematic diagnostic workflows with Instruments integration

Use when starting any iOS/Swift conversation - establishes how to find and use Axiom skills, requiring Skill tool invocation before ANY response including clarifying questions

Use when implementing SwiftUI animations, understanding VectorArithmetic, using @Animatable macro, zoom transitions, UIKit/AppKit animation bridging, choosing between spring and timing curve animations, or debugging animation behavior - comprehensive animation reference from iOS 13 through iOS 26

Use when build times are slow, investigating build performance, analyzing Build Timeline, identifying type checking bottlenecks, enabling compilation caching, or optimizing incremental builds - comprehensive build optimization workflows including Xcode 26 compilation caching

Use when writing UI tests, recording interactions, tests have race conditions, timing dependencies, inconsistent pass/fail behavior, or XCTest UI tests are flaky - covers Recording UI Automation (WWDC 2025), condition-based waiting, network conditioning, multi-factor testing, crash debugging, and accessibility-first testing patterns

Use when making design decisions, reviewing UI for HIG compliance, choosing colors/backgrounds/typography, or defending design choices - quick decision frameworks and checklists for Apple Human Interface Guidelines

Use when choosing between CloudKit vs iCloud Drive, implementing reliable sync, handling offline-first patterns, or designing sync architecture - prevents common sync mistakes that cause data loss

Use when CAAnimation completion handler doesn't fire, spring physics look wrong on device, animation duration mismatches actual time, gesture + animation interaction causes jank, or timing differs between simulator and real hardware - systematic CAAnimation diagnosis with CATransaction patterns, frame rate awareness, and device-specific behavior

Use when UI is slow, scrolling lags, animations stutter, or when asking 'why is my SwiftUI view slow', 'how do I optimize List performance', 'my app drops frames', 'view body is called too often', 'List is laggy' - SwiftUI performance optimization with Instruments 26 and WWDC 2025 patterns

Use when implementing on-device AI with Apple's Foundation Models framework — prevents context overflow, blocking UI, wrong model use cases, and manual JSON parsing when @Generable should be used. iOS 26+, macOS 26+, iPadOS 26+, visionOS 26+

Use when writing unit tests, adopting Swift Testing framework, making tests run faster without simulator, architecting code for testability, testing async code reliably, or migrating from XCTest - covers @Test/@Suite macros,

Automate git worktree creation and copy private files (not tracked in git) to new workdirs. Use when creating a new git worktree for this Flutter project that requires untracked private files like secrets.dart, Firebase configs, etc.

Use the public toolbox scripts published from docs/tools via tool-runner.js. Covers listing tools, executing them safely with droid exec context, and required environment variables.

Auto-detect project tech stacks (React, Vue, Express, Django, etc.). Recognize package managers and configuration patterns. Use when starting work on any project, analyzing dependencies, or providing framework-specific guidance.

Apply consistent security, performance, and accessibility standards across all recommendations. Use when reviewing code, designing features, or validating implementations. Cross-cutting skill for all agents.

Domain-Driven Design tactical and strategic patterns including entities, value objects, aggregates, bounded contexts, and consistency strategies. Use when modeling business domains, designing aggregate boundaries, implementing business rules, or planning data consistency.

Schema design, entity relationships, normalization, and database patterns. Use when designing database schemas, modeling domain entities, deciding between normalized and denormalized structures, choosing between relational and NoSQL approaches, or planning schema migrations. Covers ER modeling, normal forms, and data evolution strategies.

Test pyramid strategy, test design patterns, coverage analysis, and quality gate configuration. Use when designing test strategies, improving coverage, setting up automation, or defining quality gates. Covers unit, integration, and E2E testing across frameworks.

Interview techniques, persona creation, journey mapping, and usability testing patterns. Use when planning research, conducting user interviews, creating personas, mapping user journeys, or designing usability tests. Essential for user-research, requirements-analysis, and interaction-architecture agents.

Vulnerability review, OWASP patterns, secure coding practices, and threat modeling approaches. Use when reviewing code security, designing secure systems, performing threat analysis, or validating security implementations.