123 Cloud Drive (123pan) client: signs in with a phone number or email plus password, or a pasted token, browses and drag-drop uploads and downloads through a sidebar panel, backs up a workspace incrementally while keeping its directory tree, and exposes 15 tools for an agent to list, upload, download, rename, move and delete files. Network, MD5, 16MB multipart upload and token encryption run in a bundled statically linked C++ core, so it needs no Python or other runtime. Windows 10/11 x64 only.