The diagnosis prompt can be loaded from JARVIS_PROMPT_FILE so it can be tuned without rebuilding. When JARVIS_COPILOT_USER is set, the copilot child (and its MCP tree) is dropped to that unprivileged user with HOME pointed at a writable dir, so a --yolo agent cannot touch the read-only repo checkout or the service data. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 5749c447-6ecd-46bd-946d-21b4d101d084