apply-patch

# Apply Patch The built-in `edit_file` does an exact string match on a single file and has no fuzzy tolerance. For multi-file changes, or when `edit_file` keeps failing to find the string, construct a unified diff and apply it atomically with git. ## Procedure 1. Write the unified diff to a file in the sandbox (use `write_file` or a heredoc via `execute`): ``` diff --git a/path/to/file b/path/to/file --- a/path/to/file +++ b/path/to/file @@ -10,7 +10,7 @@ context line -old line +new line ``` 2. Validate before applying: `git apply --check changes.patch` 3. Apply: `git apply changes.patch` (use `-p0` if paths are not `a/`...`b/`...). 4. If `git apply` rejects the hunk, the surrounding context is stale — `read_file` the exact lines again, regenerate the diff with correct context, and retry. ## When to prefer this - Editing 3+ files for one logical change (atomic, all-or-nothing). - Repetitive or whitespace-sensitive edits where `edit_file` exact-match struggles. - Re-applying a patch produced elsewhere (e.g. from a PR or `git diff`). Always run the verify-changes skill afterwards.