I've been using Claude Desktop with built-in File MCP to run operations on local files. Sometimes it will do things directly but usually it will write a Python script. For example: combine multiple.md files into one or organize photos into folders.

I also use this method for doing code prototyping by giving it the path to files in the local working copy of my repo. Really cool to see it make changes in a vite project and it just hot reloads. Then I make tweaks or commit changes as usual.