How do you handle the fact that your AI forgets everything between sessions?

Genuinely curious how other founders deal with this.

Every time I start a new session with ChatGPT or Claude, I'm back to square one. My project context, my preferences, what I tried last week, what didn't work - all gone. I have to re-explain everything from scratch before I can get anything useful done.

I've tried a bunch of workarounds:

Keeping a "context doc" I paste in at the start of every session. Works okay but it's a chore to maintain and I always forget to update it.

Using the memory feature in ChatGPT. Better than nothing but it's shallow - it remembers surface-level stuff, not the actual nuance of how I work.

Writing very detailed system prompts. Helps for specific tasks but doesn't carry over to new conversations.

None of these feel like a real solution. They're all just workarounds for the same underlying problem: the AI has no persistent understanding of me or my work.

The thing that frustrates me most isn't even the re-explaining itself. It's that I can't build on previous sessions. Every conversation is isolated. So even if I had a really productive session last Tuesday where we figured something out together, that insight is just gone. Next session starts from zero.

I've been building something to try to solve this (an AI agent that actually accumulates knowledge from every task it runs, so it gets better over time rather than resetting) but I'm curious whether this is a pain point others feel as sharply as I do, or if most people have found ways to work around it that I'm missing.

How do you handle it? Do you have a system that actually works? Or have you just accepted it as the cost of using these tools?