I've made a very similar tool github.com/lukolszewski/session-keeper

But my tool supports pi, claude code and copilot cli as this is what I use. It also saves any tail -f and few other processes I tend to leave running for a long time as well as folders I'm in.

My tool is likewise built on top of the same tmux plugins so it saves windows layouts, names etc.

After I started using it, especially on a Windows work laptop (in WSL) that has a habit of restarting almost every night to "do updates" I don't know how could I ever live without it.

But my tool saves every few min on a schedule as well as on keystroke. I didn't need save on shutdown, because my main use case is protecting from unexpected restarts such as a mashine crash or those updates pushed by corporate it every night.

It is very cool creating such tools has become so easy one can just casually do it without spending days of time on it. That's a great benefit of AI.

Another tool I find indispensable for pi, although it's still a work in progress is my tool use permission/classified called adaptive-acl (same github account). It has a very elaborate treesitter based deterministic classification layer plus an llm feature that extracts the intent from the user context and converts it into deterministic rules.

So there is no llm call on every tool use, just those tgat don't match the deterministic rules.

My favourite feature is good level of control on the grants, ability to preview them, alter them, export, import. I also have a bajillion of my private session records that I tend to test any prompt/classifier changes so I don't get unexpected regressions.

I tend to use opus 5.5 supervisor and a team of 7 DeepSeek v4.1 Flash 1017 agents to write it (used to be Qwen3.8-Flash-Next). It does a great job, but it needs substantial architecture hand holding.