Centauri Chrome Extension

Centauri is a Chrome extension that lets you execute web tasks in natural language from a floating command shell. It is optimized for fast, visible navigation and reliable summaries. Also with extra feature to add notes to your pages. Imporve the usage of LLMs and AI agents on your daily searchs.

Developers

1. Marcos Hernanz
2. Javier Gil
3. Martí Massó
4. Marc Altabella

How The Models Are Used

• Claude (Anthropic): main agent/planner/summarizer for text and task execution.
• Gemini: image analysis path when the user submits a selected image.
• ElevenLabs: text-to-speech & speech-to-text

Configure Your Keys

Create a .env file in the project root:

ANTHROPIC_API_KEY=your_anthropic_key
GEMINI_API_KEY=your_gemini_key
GEMINI_MODEL=gemini-2.5-flash
ELEVENLABS_API_KEY=your_elevenlabs_key
ELEVENLABS_VOICE_ID=your_voice_id
ELEVENLABS_SPEECH_PROFILE=eleven_multilingual_v2

Notes:

• ANTHROPIC_API_KEY is required for the core agent experience.
• GEMINI_* is required for image-selected tasks.
• ELEVENLABS_* is required for speaker playback.
• Keys are injected at build time by scripts/build.mjs.

Build The Extension

npm install
npm run typecheck
npm run build

Build output is generated in dist/.

Load Into Chrome (Developer Mode)

1. Open chrome://extensions.
2. Enable Developer mode (top-right).
3. Click Load unpacked.
4. Select the project dist/ folder.
5. Pin the extension if needed.

After code changes:

• Run npm run build again.
• Click Reload on the extension card in chrome://extensions.

Run And Use

1. Open any page (for demo: news.ycombinator.com or mail.google.com).
2. Press Ctrl+Shift+Space (macOS: Command+Shift+Space) to open Centauri.
3. Type a prompt and press Enter.
4. Watch states progress (Planning -> Executing -> Summarizing -> result).

Suggested demo prompts:

• Summarize the top 5 hackernews articles
• Give me a summary of my last 5 unread emails

Mode behavior:

• A (Agentic): full navigation/actions.
• C (Chat): read-only DOM chat response (except hardcoded HN/Gmail flows that stay deterministic).

Optional helper commands:

npm run test:demo:hn
npm run test:demo:gmail
npm run test:perf
npm run test:rehearsal