Skills

A collection of agent skills for Claude Code, Codex, Gemini, Cursor, and more.

Available Skills

iOS

#### app-intents

Reviews and writes Swift App Intents code for Siri, Shortcuts, Spotlight, widgets, Control Center, and Apple Intelligence.

• Covers AppIntent, AppEntity, IndexedEntity, TransientAppEntity, FileEntity, and all query types (EntityQuery, EntityStringQuery, EnumerableEntityQuery, EntityPropertyQuery, IntentValueQuery)
• Handles the full snippet-intent lifecycle: ShowsSnippetView, ShowsSnippetIntent, SnippetIntent, Button(intent:), multi-step interactive confirmation
• Apple Intelligence integration via @AppIntent(schema:), @AppEntity(schema:), @AppEnum(schema:) across .photos.*, .journal.*, .mail.*, .browser.*, .visualIntelligence.*
• Widget and Control Center wiring: WidgetConfigurationIntent, ControlConfigurationIntent, App Group shared storage, WidgetCenter.reloadAllTimelines()
• Catches ~35 common mistakes LLMs make, from @Model as AppEntity to missing @Property, stale shortcut parameters, and mutation inside SnippetIntent.perform()
• Supports iOS 16+ / macOS 13+ with iOS 19+ additions (supportedModes, continueInForeground, requestChoice, snippet reload())

#### swift-format-style

Reviews and writes modern Swift FormatStyle code with .formatted() APIs.

• Covers Date, Number, Measurement, and custom FormatStyle types
• Generates correct .formatted() calls with proper modifiers
• Reviews existing FormatStyle code for best practices
• Replaces legacy DateFormatter/NumberFormatter patterns
• Supports iOS 15+ / macOS 12+ APIs

#### background-execution

Reviews and writes Swift background-execution code that runs while the app is backgrounded or suspended.

• Covers BGTaskScheduler: BGAppRefreshTask, BGProcessingTask, and BGContinuedProcessingTask (iOS 26), with registration timing, Info.plist identifiers, expiration, and setTaskCompleted
• beginBackgroundTask / endBackgroundTask assertions and ProcessInfo.performExpiringActivity for finishing in-flight work
• Background URLSession downloads and uploads, including the full handleEventsForBackgroundURLSession relaunch flow
• Silent and VoIP push, the UIBackgroundModes matrix, background audio, and the SwiftUI .backgroundTask modifier
• macOS schedulers (NSBackgroundActivityScheduler, beginActivity) and the system constraints that decide whether background work runs at all

#### widgets

Reviews and writes SwiftUI WidgetKit code across every widget surface.

• Covers all widget kinds: Home Screen, Lock Screen / accessory, and watch widgets, plus Controls (Control Center, Lock Screen, Action button), Live Activities, and the Dynamic Island
• Timeline model: TimelineProvider / AppIntentTimelineProvider, reload policies and the daily reload budget, WidgetCenter reloads, and push-updated widgets (WidgetPushHandler)
• Renders correctly in every appearance: widgetRenderingMode, widgetAccentable(), widgetAccentedRenderingMode, and the luminance-to-alpha trick for the tinted/accented Home & Lock Screen
• Interactivity and Controls: Button(intent:) / Toggle(intent:), ControlWidgetToggle (SetValueIntent) vs ControlWidgetButton, the app-process boundary, and the App Group store
• Live Activities: ActivityAttributes / ContentState, ActivityConfiguration, DynamicIsland, push (token / channel / push-to-start), and supplementalActivityFamilies for Apple Watch and CarPlay
• Spans WWDC 2020-2026 with the SiriKit .intentdefinition to App Intents and ClockKit to WidgetKit migration map, ~40 anti-patterns, and a worked end-to-end example; supports iOS 14+ / iPadOS / macOS / watchOS / visionOS

Other

#### git-codebase-preflight

Audits a repository through git history before reading source files.

• Analyzes commit frequency, active contributors, and project timeline
• Identifies hot files and recently changed areas
• Detects large files, binary assets, and repo structure
• Provides a prioritized list of files to inspect first
• Works on any Git repository without reading source code

#### ffmpeg

Categorized FFmpeg recipes for video automation pipelines, adapted from the Rendi FFmpeg cheatsheet.

• Format conversion, resize with aspect-ratio padding, frame-accurate trimming
• Audio processing: replace, extract, mix, crossfade, normalize, downsample for speech-to-text (16 kHz mono)
• Advanced editing: playback speed without pitch shift, jump cuts, social-media cropping, drawtext, subtitle burn-in, watermarking, vstack, intro/main/outro assembly
• Asset generation: image-to-video, slideshows with xfade, Ken Burns zoompan, looping GIFs, scene-change thumbnails, tiled storyboards
• Encoding tuning: CRF/preset guidance for libx264, libx265 with hvc1 for Apple AirDrop, libvpx-vp9 for the web, +faststart, hardware acceleration (*_nvenc, *_qsv, VAAPI)
• Bakes in common FFmpeg footguns: -c copy rules, input vs output seeking, setpts=PTS-STARTPTS after trim, setsar=1:1 after pad, -pix_fmt yuv420p for QuickTime

#### rich-html

Renders content as a polished, self-contained HTML deck or document instead of plain Markdown.

• Produces two single-file output profiles: a fullscreen Deck (keyboard / click / swipe navigation, progress bar, counter) and a long-scrolling Document (sections, tables, legends, inline diagrams)
• Mermaid diagrams (flowcharts, sequence, dependency graphs) themed to match the page, with the slide-visibility render gotcha already solved
• Expressive layout out of the box: cards, big-stat numbers, callout notes, pills, flow steps, and tables
• Download buttons that link the best experiment, result JSON, or full log straight from the page
• A cohesive GitHub-dark design system; ideal for recaps of long runs, showcases, pitches, architecture write-ups, reports, and specs

Installation

Any Agent (via skills.sh)

npx skills add n0an/skills

To install a single skill:

npx skills add n0an/skills --skill app-intents
npx skills add n0an/skills --skill swift-format-style
npx skills add n0an/skills --skill background-execution
npx skills add n0an/skills --skill widgets
npx skills add n0an/skills --skill git-codebase-preflight
npx skills add n0an/skills --skill ffmpeg
npx skills add n0an/skills --skill rich-html

Claude Code

/plugin marketplace add n0an/skills

Author

Anton Novoselov, https://github.com/n0an

License

The project is available under the MIT license. See the LICENSE file for more info.