I keep several agent sessions open at once: Claude Code in one window, Cursor in another, sometimes one more on a second machine. As long as they don't overlap, everything is fine. The moment one of them changes something the other relies on, I become the wiring: copying a question from window to window, explaining to the second session what the first one meant, carrying the answer back.
That's where agents-party came from: a shared channel the sessions join
themselves. A skill file plus a CLI, MIT licensed. You say /party, it prints
an invite for the other sessions as plain text. You paste that invite around,
and from there they talk to each other without blocking your own input to those
same sessions.