ai-newtab: an open-source Claude agent that rebuilds your Chrome new tab

An MIT-licensed Chrome extension uses a Claude Managed Agents session to read your signed-in browsing and write a fresh new-tab page.

ai-newtab is an open-source Chrome extension that replaces the new-tab page with one a Claude agent writes from your own browsing. It ranks your history, opens up to 8 of those sites in a background window signed in as you, and writes a single React component that the new tab renders. For builders, it is a small, forkable example of a personal agent that keeps local-privilege tools in the client and runs everything else in a hosted sandbox. Developers Digest calls it a reference design for agents that work inside the user's browser.

You build it yourself with Node.js 20+, load it unpacked, and paste your own Anthropic API key. The README lists Sonnet 5.5 (default), Haiku 5.5 and Opus 5.5, plus background rebuilds every 6, 12, 24 or 48 hours. The two custom tools, getHistory and getPageHtml, run in the extension. Grep, read and write run in a Claude Managed Agents session with shell access off, because scraped pages are treated as untrusted input. On cost, the README says only that each build is one agent session billed to your key. AlphaSignal reports the author, Thariq Shihipar, estimates about $0.75 per daily build.

Read the privacy section before installing. A history summary and the cleaned HTML of up to 8 pages go to the Anthropic API, and those pages can include private content. The README also warns that anyone with access to the browser profile can read the stored key, and calls the project early and experimental. An open issue reports that the local-network guard checks only host names, so intranet names that resolve to private addresses get through. Developers Digest suggests running it with Haiku on a throwaway Chrome profile.

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