Yo!
I made a database that is based on the old school IBM1401 punchcard system, and set a wake phrase which works in the IDE's MCP so that the state is held with just a couple hundred tokens being used to wake and continue the work!
I use multiple agents, and they all use the same database to maintain continuity. It allows me to use more than one at a time if needed(I do research) or switch between turns depending on the output required. I am using the Gemini's right now, but have used all the LLM's an a few smaller local models.
I keep the clients context separate in different directories is all. My main agent works on all my projects.
Last time something went wrong... agent said task was complete and verified but when I checked it was not "working" as planned. I suggested that there was a possibility of a reason, and my agent fixed it next run. Cost me 7 mins or so. I keep an eye on everything they do so things going wrong are typically easy fixes.
I built it using my agents, and use it all day everyday. :-) The db has some other features I built in like a context odometer and a cabinet if workflows so I dont have to teach it stuff every time.
I feel your pain, and hope you find a solid solution!
Peace!