Apple HIG Sidebars

Design and review the sidebar as the map of the app: top-level navigation only, grouped into calm sections, paired with split navigation, and safe when it collapses on compact widths. Reach for this on macOS, iPadOS, SwiftUI NavigationSplitView, AppKit source lists, UIKit split views, and productivity apps with projects, files, agents, notes, skills, tasks, or dashboards.

Core rule

Sidebar = top-level navigation
Toolbar = current-screen actions
Command palette = fast global commands
Inspector = selected-item details

A sidebar is the map of the app. It is not a dashboard and not a control panel.

Apple-style principles

1. Use sidebars for top-level navigation

Good sidebar items:

• Home
• Inbox
• Projects
• Tasks
• Files
• Agents
• Skills
• Notes
• Reports
• Settings

Avoid putting these in the sidebar:

• One-off buttons
• Deep detail content
• Destructive actions
• Dashboard widgets
• Status timelines
• Large progress cards
• Long descriptions

2. Pair the sidebar with split navigation

Preferred SwiftUI structure:

NavigationSplitView {
    SidebarView(selection: $selection)
} content: {
    ContentListView(selection: $selection)
} detail: {
    DetailView(selection: selection)
}

Use two columns for:

Sidebar → Detail

Use three columns for:

Sidebar → List → Detail

Examples:

Projects → Tasks → Task Detail
Folders → Notes → Note Editor
Agents → Runs → Run Detail

3. Keep the sidebar calm

Rules:

• Short labels
• Familiar SF Symbols
• Clear selected state
• Grouped sections
• Generous spacing
• Minimal badges
• No neon
• No large cards
• No heavy gradients

Recommended structure for an agent/task app

Command
  Home
  Active Runs
  Queue

Build
  Projects
  Skills
  Prompts
  Files

Memory
  Notes
  Decisions
  Reports

System
  Settings

Width guidance

macOS: 220–280 px
iPad: 240–320 px
Compact iPhone: collapse into NavigationStack or tab-based root

SwiftUI template

import SwiftUI

enum SidebarDestination: String, CaseIterable, Identifiable, Hashable {
    case home
    case activeRuns
    case queue
    case projects
    case skills
    case prompts
    case files
    case notes
    case decisions
    case reports
    case settings

    var id: String { rawValue }

    var title: String {
        switch self {
        case .home: "Home"
        case .activeRuns: "Active Runs"
        case .queue: "Queue"
        case .projects: "Projects"
        case .skills: "Skills"
        case .prompts: "Prompts"
        case .files: "Files"
        case .notes: "Notes"
        case .decisions: "Decisions"
        case .reports: "Reports"
        case .settings: "Settings"
        }
    }

    var symbol: String {
        switch self {
        case .home: "house"
        case .activeRuns: "bolt.circle"
        case .queue: "list.bullet.rectangle"
        case .projects: "folder"
        case .skills: "sparkles"
        case .prompts: "text.badge.star"
        case .files: "doc"
        case .notes: "note.text"
        case .decisions: "checkmark.seal"
        case .reports: "chart.bar.doc.horizontal"
        case .settings: "gearshape"
        }
    }
}

struct AppRootView: View {
    @State private var selection: SidebarDestination? = .home

    var body: some View {
        NavigationSplitView {
            SidebarView(selection: $selection)
                .navigationTitle("App")
        } detail: {
            DetailRouter(selection: selection)
        }
    }
}

struct SidebarView: View {
    @Binding var selection: SidebarDestination?

    var body: some View {
        List(selection: $selection) {
            Section("Command") {
                SidebarLink(.home)
                SidebarLink(.activeRuns, badge: "2")
                SidebarLink(.queue)
            }

            Section("Build") {
                SidebarLink(.projects)
                SidebarLink(.skills)
                SidebarLink(.prompts)
                SidebarLink(.files)
            }

            Section("Memory") {
                SidebarLink(.notes)
                SidebarLink(.decisions)
                SidebarLink(.reports)
            }

            Section("System") {
                SidebarLink(.settings)
            }
        }
        .listStyle(.sidebar)
        .frame(minWidth: 220, idealWidth: 240, maxWidth: 300)
    }

    @ViewBuilder
    private func SidebarLink(_ destination: SidebarDestination, badge: String? = nil) -> some View {
        NavigationLink(value: destination) {
            Label {
                HStack {
                    Text(destination.title)
                    Spacer()
                    if let badge {
                        Text(badge)
                            .font(.caption)
                            .foregroundStyle(.secondary)
                            .padding(.horizontal, 6)
                            .padding(.vertical, 2)
                            .background(.tertiary, in: Capsule())
                    }
                }
            } icon: {
                Image(systemName: destination.symbol)
            }
        }
        .accessibilityLabel(destination.title)
    }
}

Review checklist

[ ] Sidebar shows top-level destinations only
[ ] Items are grouped clearly
[ ] Labels are short
[ ] SF Symbols are consistent
[ ] One selected item is clear
[ ] Sidebar is quieter than main content
[ ] App works when sidebar collapses
[ ] Compact layout works on iPhone/small windows
[ ] Keyboard navigation works
[ ] Badges are used sparingly
[ ] Actions live in toolbar/menus, not sidebar
[ ] Accessibility labels are clear

Prompt template

Drop this into any coding agent (Claude Code, Codex, Cursor, …) to apply the skill:

Use the apple-hig-sidebars skill to redesign this app navigation.

Rules:
- Sidebar is for top-level navigation only.
- Use SwiftUI NavigationSplitView.
- Use List(selection:) and .listStyle(.sidebar).
- Use an enum for sidebar destinations.
- Use Label(title, systemImage:).
- Group items into clear sections.
- Keep labels short.
- Use one clear selected state.
- Move actions into toolbar or command palette.
- Make compact-width behavior safe.
- Add accessibility labels.

After coding:
- List files changed.
- Explain the new sidebar structure.
- Explain compact behavior.
- Give manual test steps.

Quality bar

I always know where I am.
I can move quickly.
The app feels organized.
The content has room to breathe.
Nothing fights for attention.