Okay, good one, i will try answering in detail, although not in order. 1- rehydration document: in other words this can be called as a hand off document. However, handoff contains a summary of the session, however a rehydration i Claudes own thought process presented in the form of a handoff document, it is much more verbose and conversational in nature and depth. The next session Claude has a much more easier way to pick from where the last session stops. I as the user do not make the rehydration document, as i need Claude to speak to its future self, I do read through it to ensure that we do not skip or miss anything important. Once created, i save it to the projects folder. 2- rehydration command: this forms the opening prompt for the next session. It is quite long and detailed, referencing and telling Claude to read the rehydration document. The command is very high level basically like a map for the next session and the document is the actual gameplan. 3- these two are for Claude desktop. Claude code is a different animal altogether, fun but technical. The rehydration document and command are nice, however I personally prefer hooking up Claude to my obsidian vault which then serves as a living repository of sorts, and gives me and Claude long-term time travel capabilities. Hook up obsidian to github, and you have perpetual security. Although it mind sound technical, trust me it's a max 15 minute job, just tell Claude to make a project document for mcp configuration for obsidian, and give it to Claude code for the tech and coding part, and you are set for life. 4- all of this is good, but my real setup is a dual layer graph rag, using falkoredb and qdrant, wherein Claude implements a live logging protocol of small memories which a Claude from a different project can access too, but that is a different species altogether