What are the minimum VPS requirements and recommended OS

OpenClaw is lightweight. For a basic Gateway + one chat channel:
Absolute minimum: 1 vCPU, 1GB RAM, ~500MB disk.
Recommended: 1-2 vCPU, 2GB RAM or more for headroom (logs, media, multiple channels). Node tools and browser automation can be resource hungry.
OS: use Ubuntu LTS (or any modern Debian/Ubuntu). The Linux install path is best tested there.
Docs: Linux, VPS hosting.