The supervisor drops to the run_as user (default llmgw-engine) when the agent is root: its credential and groups, a 0700 home under the work directory as the working directory, HOME and XDG_CACHE_HOME there. A node without the user keeps engines as root and logs why. node add creates the user in the video and render groups. Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>