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This guide walks you through using Knowledge Tooltip for the first time. You’ll go from a fresh installation to exploring all five knowledge tabs.

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Your first tooltip

1

Open any webpage

Navigate to a page with text content. Wikipedia articles, news sites, or blog posts work great.
Try this example: Open Wikipedia’s article on Artificial Intelligence
2

Highlight text

Select any word or phrase on the page (minimum 2 characters). For example, highlight “machine learning” or “neural networks”.After a brief moment (100ms), you’ll see a floating button appear above your selection with a brain icon.
3

Open the tooltip

Click the floating button to open the Knowledge Tooltip.The tooltip appears as a modal overlay with:
  • Header: “Knowledge Tooltip” title with a close button (×)
  • Tab bar: Five tabs (Summary, Define, Facts, AI, Translate)
  • Content area: Displays information for the active tab
By default, the Summary tab loads first with Wikipedia data.
The extension automatically detects the language of your selected text. If you highlight Arabic text, it will fetch Arabic Wikipedia and dictionary sources.

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Explore the tabs

Once the tooltip is open, you can explore different types of information:
The Summary tab shows Wikipedia article summaries:
  • Thumbnail image (if available from Wikipedia)
  • Article title from Wikipedia
  • Extract text: 2-3 paragraph summary
  • Read more link: Opens the full Wikipedia article in a new tab
Example: Highlight “Albert Einstein” to see his Wikipedia summary with photo, birth/death dates, and a brief biography.
// Data comes from Wikipedia REST API
// content.js:410-414
const response = await chrome.runtime.sendMessage({
  action: 'fetchWikipedia',
  term: cleanedTerm,
  language: currentLanguage
});
If the exact term isn’t found, the extension automatically searches Wikipedia for the best match using the Search API.

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Configure your preferences

Click the Knowledge Tooltip extension icon in your browser toolbar to open the settings popup:
1

Extension status

Toggle the extension on/off. When disabled, the floating button won’t appear when you highlight text.The status indicator shows:
  • ✓ Active (blue) - Extension is enabled
  • ✗ Inactive (red) - Extension is disabled
2

Language preference

Choose how the extension detects language:
  • Auto-detect (default): Automatically detects Arabic vs. English based on the selected text
  • English: Always use English sources
  • العربية (Arabic): Always use Arabic sources
// Auto-detect uses Arabic regex pattern
// content.js:140-143
function containsArabic(text) {
  const arabicRegex = /[\u0600-\u06FF\u0750-\u077F\u08A0-\u08FF]/;
  return arabicRegex.test(text);
}
3

OpenAI API key (optional)

To use AI and Translate tabs:
  1. Get an API key from platform.openai.com/api-keys
  2. Paste it in the input field (starts with sk-)
  3. Click Save
Your API key is stored locally only using chrome.storage.local and is never synced across devices.
The extension uses the gpt-5-nano model with minimal reasoning effort to keep costs low.

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Tips for effective use

Select specific terms

For best results, highlight specific nouns or terms rather than full sentences. “Marie Curie” works better than “the scientist who discovered radium”.

Use keyboard shortcuts

Press Esc to close the tooltip quickly, or click the backdrop (dark overlay) behind it.

Cached results

The extension caches the last 30 searches. If you look up the same term again, results appear instantly without fetching from the API.

Right-to-left support

When using Arabic, the entire tooltip interface switches to RTL (right-to-left) layout automatically.

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Common workflows

  1. Highlight an unfamiliar word
  2. Check the Define tab for pronunciation and meaning
  3. If you need simpler language, switch to AI tab and click “Explain Simply”
  4. Continue reading with the new knowledge
  1. Highlight the topic name (e.g., “photosynthesis”)
  2. Read the Summary tab for an overview
  3. Check Facts tab for key data points
  4. Use AI tab to ask specific questions like “How does this relate to climate change?”
  5. Click “Read more on Wikipedia” for deep dive
  1. Highlight a claim or fact you want to verify
  2. Check if Summary tab returns a Wikipedia article
  3. Look at Facts tab for structured data from Wikidata
  4. Use the “Read more” link to see full sources and citations
  1. Highlight Arabic or English text
  2. Open Translate tab
  3. Click translate to see the result
  4. Toggle back to Summary or Define tabs to learn more about the term

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What you just learned

You now know how to:
  • ✓ Highlight text and open the Knowledge Tooltip
  • ✓ Navigate between all five knowledge tabs
  • ✓ Configure language preferences and OpenAI API key
  • ✓ Use different tabs for different learning goals

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Next steps

Features Deep Dive

Learn about advanced features and tab-specific capabilities

Configuration Guide

Detailed settings and API key management

Architecture

Learn about the extension architecture

Contributing

Help improve Knowledge Tooltip

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