FSB

FSB is a local first browser automation layer that drives Chrome from natural language and exposes the same control surface to AI agents over MCP. A user states what should happen on a page and the tool carries it out, while coding agents such as Claude Code, Codex, Cursor, VS Code, Windsurf and OpenCode can call it as a server to get a real browser rather than a simulated one. Its distinguishing choice is to read the document object model instead of screenshots. The vendor contrasts this with vision driven agents and publishes its own figures of fifty to two hundred milliseconds per step and roughly $0.03 per hundred steps. Sixty actions are available, fifty three through the DOM and seven through the Chrome DevTools Protocol, covering clicks, typing, scrolling, dragging, canvas drawing, mouse control and multi tab work. Where an application exposes an authenticated API, FSB can call it directly through the logged in session and fall back to page interaction automatically. Other capabilities include reactive triggers that watch an element for a change, an autopilot mode that survives extension shutdowns and handles up to sixty four concurrent tabs with real file uploads from disk, a remote dashboard with QR code pairing and live page preview, and a memory layer shipping selectors, workflows and warnings for well over a hundred sites. No pricing is published. The site has no pricing page and no plan list, its structured data records the product at zero cost, and distribution is through an npm package installed into the chosen agent client, with a public code repository linked from the navigation.