---
title: What counts as an event
description: Each step your agent reports is one event. Size your plan with typical events-per-run numbers.
section: billing
order: 3
---

# What counts as an event

An event is each step your agent reports: a model call, a tool call, a
log line, a status update. A heartbeat ping is one event.

## Sizing your plan

Typical agents report 5 to 30 events per run. A scheduled agent running
hourly with ten steps uses around 7,300 events a month; a support agent
handling 200 conversations a day at 20 steps each uses around 120,000 a
month. Your current usage is always on the billing page.

## Size limits

- **Events can carry up to 64KB.** Larger events are accepted, with the
  largest fields shortened to fit, and shortened events are flagged in
  the dashboard so you always know.
- **Metadata is for finding things.** Each event or run can carry up to
  40 metadata keys, keys up to 128 characters, values up to 1KB, 8KB
  total. Put large content in the event body, which allows up to 64KB.
  These limits are identical on every plan and enforced at the API with
  a clear error naming the offending key: a rejected metadata key is a
  developer-time mistake that should fail loudly, not be trimmed
  silently.