Sidekick

Chat with AI about any webpage you're viewing. Sidekick adds a floating chat window that automatically reads the page content and sends it as context, so you can ask questions, get summaries, and analyze what you're reading without copying and pasting anything. On YouTube, Sidekick grabs the full video transcript with timestamps instead of the page text, so you can ask about specific parts of the video. CHOOSE YOUR AI Pick your provider in Settings and bring your own key. Use Claude (Anthropic) for the smartest answers and image understanding, or DeepSeek V4 for fast, low-cost summaries. Image and screenshot features require a Claude model. HOW IT WORKS Click the Sidekick icon on any page. A chat window opens in the bottom-right corner with the page content already loaded. Start typing. The AI already knows what's on the page. BUILT-IN COMMANDS Type /tldr to get a summary, /explain for a simple breakdown, /key for key takeaways, or /translate to translate the content. Commands also appear as clickable buttons when you first open the chat. You can edit the built-in commands or create your own in Settings. SCREENSHOT CAPTURE Click the camera button to screenshot the visible page and ask about what you see. Useful for asking about charts, layouts, diagrams, or anything visual. Requires a Claude model. TEXT-TO-SPEECH Listen to any response read aloud. Choose between free browser voices or premium ElevenLabs voices. Play, pause, and resume controls on each message. MORE FEATURES - Drag and drop images into the chat to ask about them (Claude models) - Real-time streaming responses - Markdown rendering (bold, code blocks, headers, lists, links) - Conversations auto-save as markdown files when you close a tab - Choose your AI provider and model: Claude (Opus 4, Sonnet 4, Haiku 4.5, Haiku 3.5) or DeepSeek V4 (Pro, Flash) - Custom system prompt (e.g. "always respond in Spanish") - Dark mode (auto, light, or dark) - Resizable chat window, opens at full height by default - Font selection (5 options) - Export and import your settings - Each tab has its own independent conversation PRIVACY Sidekick is designed to keep your data local. There is no server, no account, no analytics, and no tracking. - Your API keys are stored locally and never sent anywhere except their respective APIs - API calls go directly from your browser to your chosen provider (Anthropic or DeepSeek), no intermediary - No data is sent to any server operated by the developer - No browsing history or personal information is collected - Settings exports exclude API keys Full privacy policy: https://madebysan.github.io/sidekick/privacy.html REQUIREMENTS - An Anthropic API key for Claude (get one at console.anthropic.com), or a DeepSeek API key for DeepSeek V4 (platform.deepseek.com) - Optional: An ElevenLabs API key for premium text-to-speech Sidekick uses your own API key. You pay your provider directly for usage, with no subscription, no markup, and no middleman.