Two agents, one tree
One agent with a memory is a solved problem. Run a second one and something new breaks: they disagree, and neither knows it.
Your research agent decides the pricing page ships in September. Your coding agent, in a different conversation, is building against October. Both are confident, both wrote it down, and the two notes never meet. You find out in three weeks, from a calendar.
This is not a memory problem. Both remembered perfectly. It is an agreement problem, and agreement needs a place, not a bigger context.
A branch each, and one they share
The layout that works is two rules:
What is mine is mine. Each agent gets its own branch: working notes, its inbox to you, whatever it needs to think. Nobody reads anybody's scratchpad, so nobody drowns in it.
What we must agree on lives once. One shared branch, both may edit, holding decisions and open questions. A decision is one line with its reason. An open question sits there until somebody answers it, and answering moves it to Decisions.
The picture is the whole architecture. There is no coordination protocol, because the tree IS the protocol.
Why this beats making them talk to each other
The instinct is to have agents message each other. That reproduces the original problem one layer up: two conversations, two memories, no shared state, and now also a transcript nobody reads.
Shared state does what messages cannot. It is checkable: you can look at Decisions and see what your team believes. It is durable: a new agent added in October reads the same lines and starts agreeing. And it is correctable: when the September date is wrong, you fix one line and every agent inherits the fix, with no broadcast.
The rule that keeps it honest
One line for both of them: "Never silently rewrite a decision somebody else wrote. Add your own line, or move the old one to Open questions with what changed."
That single sentence is what stops shared ground becoming a place where the last writer wins, which is how shared documents usually die.
What you get to see
The quiet benefit is that disagreements become visible before they cost anything. Two agents with different beliefs produce two lines in Decisions that contradict, in the same view, where you will see them. That is not a failure of the setup; it is the setup working.
Take the team layout
Open the template, press "Show in my Pando", share the whole branch with each agent, and tell both the same sentence: "Read Shared ground first. Keep your own notes in your own branch. Never rewrite somebody else's decision."