Ask HN: Parallel agent code writers, how do you stop them from clashing quietly?

It’s getting easier to run two agent sessions in parallel over the same codebase. Avoiding them from making inconsistent assumptions, not so much.

My observations: parallel sessions acting on adjacent subsystems won't stay aligned without a common constraint set. The session that assumes the auth invariant will not know that another session just changed a constraint it relies on. The clash won’t manifest at commit time; it will occur at integration time, when the false assumption has already been propagated to three other files.

No approach feels entirely satisfactory. What works for you?