The agent's working directory is the customer's Google Drive

You sell a Drive-cleanup agent. Duplicate exports, seven versions of the same deck, folders named "final." The customer connects Drive: POST /api/v1/backends/drive registers the backend, a mount operation puts it at a path, and now the Drive is a folder in the container.

The agent has bash, read_file, list_dir. It walks the tree, hashes the duplicates, proposes a structure, and moves files with mv. It never learned the Drive API. It learned ls.

Dropbox, OneDrive, and iCloud mount the same way. One agent, one set of file tools, and whichever cloud the customer lives in shows up as a directory.

Every cloud drive is a filesystem once it's mounted, and a filesystem is a place an agent already knows how to work.