How can Claude Code, Codex, and OpenClaw share memory simultaneously? My solution is quite basic: a set of markdown files + two layers of automatic synchronization. The core is today.md. At the start of each session, it automatically reads, and at the end, it automatically writes. The OpenClaw local assistant shares the same file through a symlink, synchronizing project status, goals, and pitfall records every 5 minutes via cron, automatically generating snapshots to inject into its system prompt. Codex brings context as needed during code reviews. The memory layer is just the markdown files, not tied to any platform. I previously used Gemini as an assistant with this setup; changing models only requires modifying the target path in the synchronization script. After running for a few months, my biggest takeaway is: the value of memory synchronization lies not in "what AI remembers," but in not having to explain everything from scratch when switching tools.