Auto Browser vs Tandem Browser

Auto Browser is a free Chrome extension that uses an AI agent in the browser’s side panel. It reads a webpage’s accessibility tree and can click, type, scroll, navigate, fill forms, and handle research tasks described in plain English. Pages exposing WebMCP tools can let it use those tools instead of the page DOM. Supported providers include Chrome Built-in AI (Gemini Nano), Google Gemini, OpenRouter, and local OpenAI-compatible endpoints such as Ollama and LM Studio. You can change providers during a conversation without losing its history. Write actions require approval, arbitrary JavaScript prompts for approval, and banking, government, and healthcare origins are blocked by default. The extension is free to install at free; Google Gemini and OpenRouter charge per request using your API key. Chrome 126 or newer is required for basic use. Attachments can be images or audio up to 10 MB each.

Tandem Browser is a free, MIT-licensed browser in developer preview for running AI agents alongside a person’s browsing session. Agents share tabs, cookies, and the DOM, and can work with the accessibility tree, rendered DOM, network requests, console output, and DevTools. If an agent reaches a CAPTCHA, unclear form, or judgment call, it pauses for user help. MCP- or HTTP-speaking agents can connect locally or through a private Tailscale network, with separate workspaces and tab locks. The documented API includes more than 280 HTTP endpoints and 257 MCP tools, protected by bearer tokens. Tandem has no cloud backend, subscription, or telemetry according to its FAQ; browsing data remains on the machine unless sent elsewhere. It can run offline with Ollama or LM Studio. Daily-driver features include extensions, bookmarks, history, a local password vault, workspaces, and sidebar apps. It uses Chromium and supports macOS Apple Silicon, Windows 11 x64, and Linux on a best-effort basis.