version: "1.0.0" name: auto-brand-parity description: "Use when a product's brand must be consistent everywhere it appears — app icons across Windows, macOS, Linux, iOS, Android and the web, favicons and PWA manifests, store listings, splash screens, logos, colors and fonts; when the user mentions branding, icons, logo, favicon, app icon, brand assets, or says \"/auto-brand-parity\"; or when about to generate an icon set or call branding consistent without comparing platforms."

/auto-brand-parity

Establish what this product's brand actually is, then make every platform agree with it — and say plainly where an asset is missing, wrong-sized, or derived from the wrong master.

The failure this exists for: the website has the current logo, the Android icon is two versions old, the macOS icon was exported from a screenshot, the store listing uses a third blue, and nothing is broken enough to notice until they sit side by side.

Step 1 — Establish The Brand (interactive by default)

Ask before assuming, and ask for artifacts rather than descriptions:

1. A vector master. SVG, AI, PDF, or a Figma frame. Everything below derives from it. **A raster

logo caps the quality ceiling permanently** — at 16px an upscaled PNG is mush and there is no recovering it. If none exists, say so as a finding and offer to trace or rebuild one.

1. The palette, as values: brand color, accent, background, and the light/dark variants.
2. Fonts, and — the part that gets skipped — whether they are licensed for embedding in an

app, which is a different grant from web use.

1. A monochrome / single-color variant, which several platforms require and nobody has ready.
2. Existing brand guidelines, clear-space and minimum-size rules if they exist.
3. A media/reference folder if the user has one, for inspiration or actual assets to use.

If the user has none of this, derive a candidate from the most load-bearing existing asset, show what you derived, and get one confirmation before generating anything from it.

Step 2 — Inventory What Exists

Find every asset the product ships, per platform, with its real dimensions:

rg --files -g '{*.ico,*.icns,*.iconset,*.png,*.svg,*.webp,*.jpg}' \
   -g '{**/AppIcon.appiconset/**,**/mipmap-*/**,**/res/drawable*/**,**/Assets.xcassets/**}' \
   -g '{**/public/**,**/static/**,**/build/icons/**,**/snap/gui/**}' -g '!node_modules' -g '!.git'
 
identify -format '%f %wx%h %[colorspace]\n' path/to/*.png     # ImageMagick
file *.ico *.icns

Then compare them against each other, not just against the spec: same artwork? same palette? same version? Extract the dominant colors from each rendered icon and diff them — three blues across app, site and store listing is the classic finding and it is invisible unless you measure.

Step 3 — Platform Requirements

Where the spec is fixed, hold to it exactly.

Windows

.ico must contain, at minimum, 16, 24, 32, 48, 256. Add 20 and 40 — Windows resolves by exact match, then takes the next size up and scales down, never up, so 125% and 250% displays fall back to 24 and 48 and look soft. That is the "fuzzy only on this laptop" bug. Alt+Tab wants a 40. Only the 256 entry should be PNG-compressed; compressing the rest saves nothing and uncompressed 256 bloats the file.

MSIX/Store, if packaging: Square44x44Logo and Square150x150Logo at minimum 100/200/400% scale, plus AppList.targetsize-* at 16/20/24/30/32/36/40/48/60/64/72/80/96/256 — and the `_altform-unplated` variants, without which every user gets a grey plate behind the icon in the taskbar with no build warning. Use altform-lightunplated for light theme; never combine `theme-light` with `altform-unplated`. The Store still requires MedTile scale-100 and StoreLogo even though Windows 11 ignores tiles.

macOS

.iconset filenames are the API, and they are point-based:

icon_16x16.png=16   icon_16x16@2x.png=32    icon_32x32.png=32    icon_32x32@2x.png=64
icon_128x128.png=128  icon_128x128@2x.png=256  icon_256x256.png=256
icon_256x256@2x.png=512  icon_512x512.png=512  icon_512x512@2x.png=1024
iconutil -c icns -o MyIcon.icns MyIcon.iconset

There is no `icon_1024x1024.png` — the 1024 slot is icon_512x512@2x.png, and writing the former gets it silently ignored. Getting the point-vs-pixel mapping backwards builds fine and looks blurry.

Current macOS icons are layered, 1024×1024, square and unmasked. The system applies the rounded rectangle. Pre-applying the mask, a drop shadow, or blur breaks the system's specular highlights and produces jagged edges — ship flat, square, shadow-free layers. Color spaces: sRGB, Gray Gamma 2.2, or Display P3.

Linux

Install into the hicolor theme at the standard sizes (16, 22, 24, 32, 36, 48, 64, 72, 96, 128, 192, 256, 512, plus @2 variants), because icon lookup short-circuits per theme — one 16px icon in your theme beats a 512px icon in a parent theme, so a partial ladder is worse than none.

.desktop Icon= takes a name without extension when it is not an absolute path. Flatpak wants /app/share/icons/hicolor/$size/apps/$APPID.png with a reverse-DNS app id (dashes only in the last component). AppImage requires AppRun, .DirIcon, and exactly one .desktop file in the AppDir root. Snap takes snap/gui/icon.svg, 40×40 to 512×512, 256×256 recommended, under 256 KB.

Mobile and stores — discover, do not assume

These specs move between OS releases, and a stale dimension table is worse than none. Read the requirement from the toolchain rather than from memory, then validate:

• iOS: the asset catalog / Icon Composer set in the project is the authority; build and let Xcode

report what is missing. Note the alpha-channel prohibition for App Store icons, and the modern dark/tinted variants.

• Android: adaptive icons have a foreground/background layer with a safe zone — a logo drawn to the

full canvas gets cropped by the circular mask. Generate through Android Studio's Image Asset tool or flutter_launcher_icons/tauri icon and inspect the result at mask boundaries. Provide the monochrome layer for themed icons or the icon vanishes on some launchers.

• Stores: pull the current requirements from the console/API and diff your assets against them, rather

than trusting a table.

Where you cannot confirm a dimension, say so and check it — never emit an icon set built on a guessed spec.

Web

Favicon set, apple-touch-icon, and a web app manifest with a `maskable` icon (its safe zone is smaller than the canvas — a full-bleed logo gets cropped on Android). theme-color, including its prefers-color-scheme form. Open Graph and Twitter card images. An SVG favicon needs explicit dark-mode handling; it does not adapt on its own.

Step 4 — Generate From The Master, Never From A Sibling

Every derived asset comes from the vector master at its target size. Never upscale, and never regenerate one platform's icon from another platform's PNG — that compounds resampling and drifts the palette.

Downscale with awareness: a logo with fine detail turns to mush at 16px. The correct answer is a simplified mark for small sizes, not a sharper resampler. Check the small sizes visually, at 100%, on both light and dark backgrounds.

Watch the color pipeline: sRGB vs Display P3 shifts, hex values taken from a print palette, and gamma shifts introduced by naive downscaling.

Step 5 — Verify By Looking

Render every generated icon at its real target size and actually view it — in a grid, light and dark, next to the current website logo and store listing. Cohesion is only visible in comparison.

Check specifically: mask cropping at circular and squircle boundaries, legibility at the smallest size, the monochrome variant against both backgrounds, and whether the brand color used as a UI accent still clears contrast requirements (hand that check to /auto-ui-ux).

Step 6 — Report

.audit/brand-report.md: per platform, per asset — present/missing, actual vs required dimensions, which master it derives from, and whether it matches the current brand. Flag anything derived from a raster source or from another platform's export.

Include what you could not verify and why. Then list the regeneration commands, and ask before overwriting any existing asset — a hand-tuned small icon is often better than a generated one, and overwriting it silently is a real loss.

Rationalization Table

Red Flags — Stop

• Generating any icon set from a raster source without flagging it
• Emitting a dimension you did not verify against the toolchain or the current spec
• Regenerating one platform's assets from another platform's export
• Pre-applying platform masking, rounding, or shadows
• Shipping an adaptive icon without checking it under the mask
• Overwriting an existing hand-tuned asset without asking
• Declaring brand consistency without rendering the platforms side by side
• Ignoring the monochrome/themed variant because the color one looks fine