What
When an eval case defines a scaffold_script (author-supplied setup code) but the --scaffold flag wasn't used, Claude Code now prints an explicit warning that the script won't run and that the case will execute against an unstaged workspace, rather than skipping it silently.
Why
This makes it clear when a case is running without its intended setup, and reminds you that --scaffold runs author-supplied bash code as you, so it should only be passed for eval suites you trust.
Names in the bundle--scaffoldscaffold_script
Documented inclaude-code/plugin-evals
--scaffold
Plugins reference modified, high confidence
| `--scaffold` | Run each case's [`scaffold_script`](/docs/en/plugin-evals#add-setup-or-history-with-case-yaml) | Off |see the edit
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Confirmed since
Anthropic's documentation has since written up scaffold_script, on Test plugins with evals.
* **Fixture files or a git repository**: write a Bash script in the case directory and name it in `context.scaffold_script`. The script runs as you, outside the agent's sandbox, and only when you pass `--scaffold`, so pass that flag only f…plugin-evals see the edit
Confirmed since
Anthropic's documentation has since written up --scaffold, on Test plugins with evals.
* **Fixture files or a git repository**: write a Bash script in the case directory and name it in `context.scaffold_script`. The script runs as you, outside the agent's sandbox, and only when you pass `--scaffold`, so pass that flag only f…plugin-evals see the edit
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agrees
--scaffold on Plugins reference