ather than just editing DOM via JS in console the agent is treating the page, and the DOM as a file.

The models are often trained in RL sandboxes with full access to the filesystem and bash, so they are really good at using it. So to make the agent behave well, I've simulated this environment.

The whole state of a page and scripts is implemented as a virtual filesystem hacked on top of browser.local storage. URL is mapped to directories, and the agent starts inside this directory. It has the tools to read/edit files, grep around and a fake bash command that is just used for running scripts and executing JS code.

I've tested only with Opus 4.5 so far, and it works pretty reliably. The state of the file system can be synced to the real filesystem, although because Firefox doesn't support Filesystem API, you need to manually import the fs contents first.

This agent is really useful for extracting things to CSV, but it's also can be used for fun.

Demo: https://x.com/ichebykin/status/201568697443960860718:T472,Handing over the FreeCAD Beginner's Handbook to Prusa

Today, Marcel Ehlers from Prusa Research was at my place in Sankt Augustin, Germany, to personally take delivery of their own copy of the FreeCAD Beginner's Handbook, including a handwritten dedication to the Prusa-team and to Josef Prusa personally.

Prusa has sponsored the FreeCAD Beginner's Handbook to further support the maker community and to embrace inventions in mechanical engineering. By combining a Prusa 3D-printer and FreeCAD, one can design and manufacture prototypes of their invention at home and within just one day.

Marcel left his Prusa CORE One+ for me to print out the Mars Rover from the book and to play around with it. We discussed the recent developments in and around manufacturing and what that future means for us.

Next, the book will be shown around

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