Show HN: No ads and noise from any page, get a clean AI reformat in one click

cwsum

A Chrome extension that summarizes and reformats any webpage with AI — with full bilingual support for English and Chinese output.

cwsum is a Manifest V3 extension that opens a clean right-side panel on any webpage. Choose TL;DR for bullet-point takeaways or Reformat for a clean, readable Markdown version of the full page with images, links, and tables preserved. Both modes support English and Chinese output, streaming results word-by-word as the AI generates them. Your API key stays on your machine — no analytics, no intermediary servers.

One click

Open the side panel from the toolbar or Cmd+Shift+S

Your API key

DeepSeek or OpenAI. Key stored in Chrome, never leaves your box

Manifest V3

Modern Chrome extension. No build step, vanilla JS, ~15 source files

⤓ Download cwsum.zip

Chrome 116+ · Manifest V3

67 KB · zip archive · load unpacked in chrome://extensions

The side panel — language selector, cache badge, and a Markdown-rendered AI summary.

Cached result — instant reload with relative timestamp.

Options — API key, model, and endpoint configuration.

Reformat mode — full-page Markdown with images, links, and tables preserved.

What it is

cwsum is a Chrome extension that puts AI summarization one click away on any webpage. Click the toolbar icon (or press Cmd+Shift+S) and the side panel opens with a structured summary of whatever you’re reading. The extension extracts the page’s visible text — stripping out navigation, sidebars, ads, and scripts — and sends it to the AI endpoint you configure.

Your API key lives in chrome.storage.sync and is never sent anywhere except directly to the API endpoint you specify. The extension has no analytics, no tracking, and no intermediate server. It is a thin client between your browser and your AI provider. Page content goes from your tab to the model; the summary goes from the model to the side panel. Nothing else happens.

Features

AI-powered summaries

Extracts page content and produces concise, structured summaries with key points, notable facts, and main takeaways. Works on articles, documentation, research papers, and any text-heavy page.

Two modes, one panel

TL;DR gives you bullet-point takeaways in under 200 words. Reformat restructures the entire page as clean Markdown with images, links, and tables preserved — like a reader-mode that keeps the good parts. Both stream results live as they’re generated.

Bilingual output

Toggle between English and Chinese (中文) output with a single click. Each language gets its own cache entry — switch freely without losing results.

Smart caching

Revisiting a page shows the cached summary instantly with no API call. A Cached badge tells you it came from local storage, with a relative timestamp (“3m ago”). Click the refresh button to force a fresh fetch.

Markdown + highlighting

Summaries render with full GitHub-flavored Markdown: headings, bullet lists, blockquotes, tables, and links. Fenced code blocks get syntax highlighting via highlight.js with a clean GitHub theme.

Keyboard shortcut

Open the side panel without touching the mouse: ⌘ShiftS on Mac, CtrlShiftS on Windows and Linux.

Configurable model

Set any OpenAI-compatible model in the Options page. Defaults to deepseek-v4-flash, the cheapest DeepSeek model at $0.14/M input tokens. Also works with OpenAI, Anthropic endpoints, or any compatible API.

Keyboard

Everything is reachable from the keyboard or a single click.

⌘ShiftS / CtrlShiftSOpen the side panel

Click extension iconOpen the side panel

Language dropdownSwitch between English and Chinese

Mode tabsSwitch between TL;DR and Reformat modes in the panel header

Refresh button 🔄Re-summarize — skip cache, fresh API call

Right-click icon → OptionsSet API key, model, and default language

FAQ

Which AI models does it support?

Any OpenAI-compatible chat completions endpoint. It ships with deepseek-v4-flash as the default — the cheapest DeepSeek model at $0.14/M input tokens. You can change the model name and API base URL in the extension Options.

Is my data safe?

Your API key is stored in Chrome’s encrypted sync storage and is only sent to the API endpoint you configure. The extension has no analytics, no tracking, and no intermediate server. Page content goes directly from your browser to your AI provider.

What gets sent to the AI?

The page title, URL, and up to 12,000 characters of visible body text (with navigation, sidebars, ads, and scripts stripped out). The extraction is trimmed to keep API costs low.

Can I use it with OpenAI instead of DeepSeek?

Yes. Change the model to gpt-4o-mini and update the API endpoint URL if your OpenAI base URL differs. The extension uses the standard chat completions format.

Is it open source?

Yes. The full source is ~15 files, vanilla JS, no build step, no framework. Available on GitHub.

Install & use

cwsum is a Chrome Manifest V3 extension. It runs in any Chromium-based browser (Chrome 116+, Edge, Brave, Arc). Load it once and it stays out of your way.

⤓ Download cwsum.zip

Chrome 116+ · Manifest V3 · 67 KB

Unzip to a permanent folder, open chrome://extensions, enable Developer mode, click Load unpacked, and select the folder. Then right-click the icon → Options to set your API key.