What is a Command Queue?

Instead of executing an instruction the instant it's received, a system with a command queue writes it to a durable store first — so if the worker crashes mid-task, restarts, or is temporarily overloaded, the instruction isn't lost; it's still sitting in the queue waiting to be picked up. This is the same pattern behind job queues and message brokers generally, applied specifically to sequences of commands an agent or automation needs to carry out. Queues also enable lanes: separating high-priority interactive commands from background batch work so a user waiting on a live response isn't stuck behind a long-running scheduled job. Ordering guarantees matter too — some queues process strictly first-in-first-out, others allow priority reordering, and getting this wrong can mean a cancellation command executes before the action it was meant to cancel. For multi-agent systems specifically, a command queue is what lets several agents or processes submit work concurrently without stepping on each other, since each command is a discrete, retryable unit rather than a live in-memory call that vanishes on failure.