Local Apply Patch workspace

Apply Patch asks your Python code to make each file change. LocalWorkspace is a working implementation you can copy when those changes should stay inside one directory.

Download apply_patch_workspace.py, then put it beside your application.

from pathlib import Path

from chatsnack import Chat, utensil
from apply_patch_workspace import LocalWorkspace

workspace = LocalWorkspace(Path("my-project"))
patch = utensil.apply_patch(execute=workspace.apply_patch)

editor = Chat(
    "Edit only files inside the project.",
    utensils=[patch],
)

edited = editor.chat("In menu.txt, replace `kettle corn` with `caramel corn`.")
print(edited.last)

The directory must already exist. Choosing it is the permission decision: once the utensil is attached, the chat may create, update, or delete UTF-8 text files anywhere below that directory.

The example follows the operation-level V4A format described in OpenAI's Apply Patch guide. That contract was checked on August 22, 2026. The code refuses absolute paths, .. traversal, symlinks, directory targets, and patches whose context no longer matches the file. An update is written only after the entire diff parses successfully.

Each operation finishes independently. If a later operation fails, earlier changes remain on disk. Add your application's approvals, evidence, backups, and recovery around workspace.apply_patch. For hostile or concurrently modified workspaces, use an operating-system sandbox as well.