Imported from diegosouzapw/awesome-omni-skills (skills/favicon/SKILL.md). Install upstream with npx skills add diegosouzapw/awesome-omni-skills --skill favicon. Copyright stays with the author.

favicon

Overview

This public intake copy packages plugins/antigravity-awesome-skills-claude/skills/favicon from https://github.com/sickn33/antigravity-awesome-skills into the native Omni Skills editorial shape without hiding its origin.

Use it when the operator needs the upstream workflow, support files, and repository context to stay intact while the public validator and private enhancer continue their normal downstream flow.

This intake keeps the copied upstream files intact and uses the external_source block in metadata.json plus ORIGIN.md as the provenance anchor for review.

Generate a complete set of favicons from the source image at $1 and update the project's HTML with the appropriate link tags.

Imported source sections that did not map cleanly to the public headings are still preserved below or in the support files. Notable imported sections: Prerequisites, Error Handling, Limitations.

When to Use This Skill

Use this section as the trigger filter. It should make the activation boundary explicit before the operator loads files, runs commands, or opens a pull request.

• You need to generate a complete favicon set from a single source image.
• The task includes placing the assets in the correct framework-specific static directory and updating HTML link tags.
• You want one workflow that validates the source image, detects the project type, and writes the right favicon outputs.
• Use when the request clearly matches the imported source intent: Generate favicons from a source image.
• Use when the operator should preserve upstream workflow detail instead of rewriting the process from scratch.
• Use when provenance needs to stay visible in the answer, PR, or review packet.

Operating Table

Workflow

This workflow is intentionally editorial and operational at the same time. It keeps the imported source useful to the operator while still satisfying the public intake standards that feed the downstream enhancer flow.

1. Verify the source image exists at the provided path: $1
2. Check the file extension is a supported format (PNG, JPG, JPEG, SVG, WEBP, GIF)
3. If the file doesn't exist or isn't a valid image format, report the error and stop
4. Framework - Detection - Static Assets Directory
5. Rails - config/routes.rb exists - public/
6. Next.js - next.config.* exists - public/
7. Gatsby - gatsby-config.* exists - static/

Imported Workflow Notes

Imported: Step 1: Validate Source Image

1. Verify the source image exists at the provided path: $1
2. Check the file extension is a supported format (PNG, JPG, JPEG, SVG, WEBP, GIF)
3. If the file doesn't exist or isn't a valid image format, report the error and stop

Note whether the source is an SVG file - if so, it will also be copied as favicon.svg.

Imported: Step 2: Detect Project Type and Static Assets Directory

Detect the project type and determine where static assets should be placed. Check in this order:

Important: If existing favicon files are found (e.g., favicon.ico, apple-touch-icon.png), use their location as the target directory regardless of framework detection.

Report the detected project type and the static assets directory that will be used.

When in doubt, ask: If you are not 100% confident about where static assets should be placed (e.g., ambiguous project structure, multiple potential locations, unfamiliar framework), use AskUserQuestionTool to confirm the target directory before proceeding. It's better to ask than to put files in the wrong place.

Imported: Step 3: Determine App Name

Find the app name from these sources (in priority order):

1. Existing site.webmanifest - Check the detected static assets directory for an existing manifest and extract the name field
2. package.json - Extract the name field if it exists
3. Rails config/application.rb - Extract the module name (e.g., module MyApp → "MyApp")
4. Directory name - Use the current working directory name as fallback

Convert the name to title case if needed (e.g., "my-app" → "My App").

Imported: Step 4: Ensure Static Assets Directory Exists

Check if the detected static assets directory exists. If not, create it.

Imported: Step 5: Generate Favicon Files

Run these ImageMagick commands to generate all favicon files. Replace [STATIC_DIR] with the detected static assets directory from Step 2.

Important: The -background none flag must come BEFORE the input file to properly preserve transparency when rendering SVGs. Placing it after the input will result in a white background.

favicon.ico (multi-resolution: 16x16, 32x32, 48x48)

magick -background none "$1" \
  \( -clone 0 -resize 16x16 \) \
  \( -clone 0 -resize 32x32 \) \
  \( -clone 0 -resize 48x48 \) \
  -delete 0 -alpha on \
  [STATIC_DIR]/favicon.ico

favicon-96x96.png

magick -background none "$1" -resize 96x96 -alpha on [STATIC_DIR]/favicon-96x96.png

apple-touch-icon.png (180x180)

magick -background none "$1" -resize 180x180 -alpha on [STATIC_DIR]/apple-touch-icon.png

web-app-manifest-192x192.png

magick -background none "$1" -resize 192x192 -alpha on [STATIC_DIR]/web-app-manifest-192x192.png

web-app-manifest-512x512.png

magick -background none "$1" -resize 512x512 -alpha on [STATIC_DIR]/web-app-manifest-512x512.png

favicon.svg (only if source is SVG)

If the source file has a .svg extension, copy it:

cp "$1" [STATIC_DIR]/favicon.svg

Imported: Step 6: Create/Update site.webmanifest

Create or update [STATIC_DIR]/site.webmanifest with this content (substitute the detected app name):

{
  "name": "[APP_NAME]",
  "short_name": "[APP_NAME]",
  "icons": [
    {
      "src": "/web-app-manifest-192x192.png",
      "sizes": "192x192",
      "type": "image/png",
      "purpose": "maskable"
    },
    {
      "src": "/web-app-manifest-512x512.png",
      "sizes": "512x512",
      "type": "image/png",
      "purpose": "maskable"
    }
  ],
  "theme_color": "#ffffff",
  "background_color": "#ffffff",
  "display": "standalone"
}

If site.webmanifest already exists in the static directory, preserve the existing theme_color, background_color, and display values while updating the name, short_name, and icons array.

Imported: Step 7: Update HTML/Layout Files

Based on the detected project type, update the appropriate file. Adjust the href paths based on where the static assets directory is relative to the web root:

• If static files are in public/ or static/ and served from root → use /favicon.ico
• If static files are in src/assets/ → use /assets/favicon.ico
• If static files are in the same directory as HTML → use ./favicon.ico or just favicon.ico

For Rails Projects

Edit app/views/layouts/application.html.erb. Find the <head> section and add/replace favicon-related tags with:

<link rel="icon" type="image/png" href="/favicon-96x96.png" sizes="96x96" />
<link rel="icon" type="image/svg+xml" href="/favicon.svg" />
<link rel="shortcut icon" href="/favicon.ico" />
<link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
<meta name="apple-mobile-web-app-title" content="[APP_NAME]" />
<link rel="manifest" href="/site.webmanifest" />

Important:

• If the source was NOT an SVG, omit the <link rel="icon" type="image/svg+xml" href="/favicon.svg" /> line
• Remove any existing <link rel="icon", <link rel="shortcut icon", <link rel="apple-touch-icon", or <link rel="manifest" tags before adding the new ones
• Place these tags near the top of the <head> section, after <meta charset> and <meta name="viewport"> if present

For Next.js Projects

Edit the detected layout file (app/layout.tsx or src/app/layout.tsx). Update or add the metadata export to include icons configuration:

export const metadata: Metadata = {
  // ... keep existing metadata fields
  icons: {
    icon: [
      { url: '/favicon.ico' },
      { url: '/favicon-96x96.png', sizes: '96x96', type: 'image/png' },
      { url: '/favicon.svg', type: 'image/svg+xml' },
    ],
    shortcut: '/favicon.ico',
    apple: '/apple-touch-icon.png',
  },
  manifest: '/site.webmanifest',
  appleWebApp: {
    title: '[APP_NAME]',
  },
};

Important:

• If the source was NOT an SVG, omit the { url: '/favicon.svg', type: 'image/svg+xml' } entry from the icon array
• If metadata export doesn't exist, create it with just the icons-related fields
• If metadata export exists, merge the icons configuration with existing fields

For Static HTML Projects

Edit the detected index.html file. Add the same HTML as Rails within the <head> section.

If No Project Detected

Skip HTML updates and inform the user they need to manually add the following to their HTML <head>:

<link rel="icon" type="image/png" href="/favicon-96x96.png" sizes="96x96" />
<link rel="icon" type="image/svg+xml" href="/favicon.svg" />
<link rel="shortcut icon" href="/favicon.ico" />
<link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
<meta name="apple-mobile-web-app-title" content="[APP_NAME]" />
<link rel="manifest" href="/site.webmanifest" />

Imported: Step 8: Summary

Report completion with:

• Detected project type and framework
• Static assets directory used
• List of files generated
• App name used in manifest and HTML
• Layout file updated (or note if manual update is needed)
• Note if any existing files were overwritten

Imported: Prerequisites

First, verify ImageMagick v7+ is installed by running:

which magick

If not found, stop and instruct the user to install it:

• macOS: brew install imagemagick
• Linux: sudo apt install imagemagick

Examples

Example 1: Ask for the upstream workflow directly

Use @favicon to handle <task>. Start from the copied upstream workflow, load only the files that change the outcome, and keep provenance visible in the answer.

Explanation: This is the safest starting point when the operator needs the imported workflow, but not the entire repository.

Example 2: Ask for a provenance-grounded review

Review @favicon against metadata.json and ORIGIN.md, then explain which copied upstream files you would load first and why.

Explanation: Use this before review or troubleshooting when you need a precise, auditable explanation of origin and file selection.

Example 3: Narrow the copied support files before execution

Use @favicon for <task>. Load only the copied references, examples, or scripts that change the outcome, and name the files explicitly before proceeding.

Explanation: This keeps the skill aligned with progressive disclosure instead of loading the whole copied package by default.

Example 4: Build a reviewer packet

Review @favicon using the copied upstream files plus provenance, then summarize any gaps before merge.

Explanation: This is useful when the PR is waiting for human review and you want a repeatable audit packet.

Best Practices

Treat the generated public skill as a reviewable packaging layer around the upstream repository. The goal is to keep provenance explicit and load only the copied source material that materially improves execution.

• Keep the imported skill grounded in the upstream repository; do not invent steps that the source material cannot support.
• Prefer the smallest useful set of support files so the workflow stays auditable and fast to review.
• Keep provenance, source commit, and imported file paths visible in notes and PR descriptions.
• Point directly at the copied upstream files that justify the workflow instead of relying on generic review boilerplate.
• Treat generated examples as scaffolding; adapt them to the concrete task before execution.
• Route to a stronger native skill when architecture, debugging, design, or security concerns become dominant.

Troubleshooting

Problem: The operator skipped the imported context and answered too generically

Symptoms: The result ignores the upstream workflow in plugins/antigravity-awesome-skills-claude/skills/favicon, fails to mention provenance, or does not use any copied source files at all. Solution: Re-open metadata.json, ORIGIN.md, and the most relevant copied upstream files. Check the external_source block first, then restate the provenance before continuing.

Problem: The imported workflow feels incomplete during review

Symptoms: Reviewers can see the generated SKILL.md, but they cannot quickly tell which references, examples, or scripts matter for the current task. Solution: Point at the exact copied references, examples, scripts, or assets that justify the path you took. If the gap is still real, record it in the PR instead of hiding it.

Problem: The task drifted into a different specialization

Symptoms: The imported skill starts in the right place, but the work turns into debugging, architecture, design, security, or release orchestration that a native skill handles better. Solution: Use the related skills section to hand off deliberately. Keep the imported provenance visible so the next skill inherits the right context instead of starting blind.

Related Skills

• @00-andruia-consultant - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @00-andruia-consultant-v2 - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @10-andruia-skill-smith - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @10-andruia-skill-smith-v2 - Use when the work is better handled by that native specialization after this imported skill establishes context.

Additional Resources

Use this support matrix and the linked files below as the operator packet for this imported skill. They should reflect real copied source material, not generic scaffolding.

Imported Reference Notes

Imported: Error Handling

• If ImageMagick is not installed, provide installation instructions and stop
• If the source image doesn't exist, report the exact path that was tried and stop
• If ImageMagick commands fail, report the specific error message
• If the layout file cannot be found for HTML updates, generate files anyway and instruct on manual HTML addition

Imported: Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.