ExecuteArtifact

Machine-readable metadata attached to an execute tool result.

Carried on ToolMessage.artifact alongside the model-facing content, so callers can react to shell failures. artifact is None instead when no command ran -- a validation or unsupported-backend error, where ToolMessage.status is "error".

Note that status is "success" for any command that ran, including one that exited non-zero: the model is expected to read the output and decide what to do. Use exit_code, not status, to detect command failure.