Filesystem Tools

Filesystem capabilities let DuckAgent inspect and change workspace files when policy allows it.

Common actions include:

• Read a file.
• Search file names.
• Search file contents.
• Write a file.
• Edit a file.
• Apply a patch.

Path-aware filesystem actions can trigger AGENTS.md discovery for the target path. Sandbox filesystem rules still decide whether the operation is allowed, needs approval, or is denied.

Rewind Snapshots

When write_file, edit, or apply_patch changes a file inside a session, DuckAgent records a before/after snapshot entry in the session log. The user can later run /rewind to list rewind points and /rewind <number> to return to before a user turn.

Tracked file changes are restored only when the current file still matches the recorded after-change checksum. If the file was edited later by a user, shell command, editor, or another Agent turn, DuckAgent skips that restore and reports a warning instead of overwriting the newer state.

User expectation

You usually do not need to configure filesystem tools directly. Configure the Sandbox when you want to change where tools may read or write.