You can achieve this by externalizing the memory outside of every harness and then connecting all harnesses to it via MCP.
Then you will have a single store where you can both read and write, and nothing will need to be synced.
I am the founder of Substrate, a project that aims to provide this capability: having just one memory for all your agents, sessions and tools.
What two harnesses do you switch between most often?
Not memory, rather the sessions and skills. So you start your session in opencode on linux with say sol model, then the next hour you pull your Mbp start claude code on macos and cont the session on opus, with the same skills too. Memory isn’t that useful I found it actually bad as it impacts the output in a different direction than what was asked. I was thinking to build it but didn’t have the time, if something proven exists and open source (to trust it with sessions) then that would be great.
We don't move session / skill files between tools.
Instead the next tool gets the decisions from the last session, as well as the sources they were based on.
The plugins are open source (MIT), the server isn't, and there's no self-hosted version yet.
Is it enough to have the decisions and open questions, or do you need the full transcript?
If the skill wa already loaded into context tranplanting it into a new harness will move that skills context as well (not the scripts though).
What kind of memory has degraded your performance?
Memory is quite tricky to tune and simple a direct implementations of an LLM Wiki concept can indeed have a lot of problems, as context accumulates.
> start your session in ... then ... cont the session on
This is not a technical restriction, but a commercial one. Any vendor agnostic harness can implement session sharing as a feature, but because you would be made to pay higher token pricing, there will be little interest among the consumers.
You can do session sharing in proprietary harnesses as well - we do that at Substrate.
Sessions are just text - and can be manipulated however you want.
lmk if you want a quick onboarding to trysubstrate.co
I am the founder of Substrate, a project that aims to provide this capability: having just one memory for all your agents, sessions and tools.
What two harnesses do you switch between most often?