The shell's stderr was discarded, so a shell that could not start looked like an immediate disconnect. It now goes to the terminal like other output, followed by the exit code. An end-to-end test covers a machine with no shell. Builds against Bamboo v0.1.10, which says why when there is no shell to run. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>