Nebula Spotlight

Nebula Spotlight: Your AI copilot that answers, plans, and acts instantly privacy-first, anywhere on the chromium browsers.

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Inspiration

The modern web is overwhelming too many tabs, scattered workflows, and constant context switching.
We wanted an AI copilot that lives inside the browser and makes information flow seamless, without sacrificing privacy.

What it does

Nebula Spotlight is a "Chrome MV3 extension" that acts as an AI copilot for the browser.With a single keyboard shortcut, you can "Ask" questions about the page, "Plan" safe step-by-step actions, and "Go" anywhere with a Spotlight-style command palette. It transforms scattered browsing into a focused, privacy-first experience.

How we built it

  • Frontend: React + TypeScript Chrome extension (MV3 service worker model).
  • Backend: Cloudflare Workers proxy with KV caching for low-latency answers.
  • AI Layer: Gemini as the primary LLM, Workers AI as fallback.
  • Privacy: Context trimming + PII masking so sensitive data never leaves the browser.
  • Design: Minimal, distraction-free interface with quick keyboard access.

Challenges we ran into

  • Working within MV3 constraints(service workers, background messaging, stricter permissions).
  • Handling token limits while still keeping enough context for accurate answers.
  • Designing graceful fallbacks when Gemini isn’t available.
  • Creating a native-feeling UX that blends into any website.

Accomplishments that we're proud of

  • Achieved a median response time under 1.5s with caching.
  • Built a site-agnostic extension that works everywhere without breaking pages.
  • Designed a privacy-first workflow that puts user trust before features.
  • Delivered a clean, hackathon-ready demo experience with real-time AI answers.

What we learned

  • How to balance AI accuracy with speed using KV cache + edge workers.
  • The importance of structured AI outputs (JSON planning) for reliability.
  • Deep dive into Chrome MV3 development and extension UX patterns.
  • How to frame AI features around trust and privacy, not just functionality.

What's next for Nebula Spotlight

  • Release to the Chrome Web Store with polished branding.
  • Add cross-browser support (Firefox, Edge).
  • Integrate optional sponsor features like Snowflake analytics and GoDaddy domain polish.
  • Explore team workflows: shared Spotlight prompts and collaborative task plans.

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