Error count over time, bucketed hourly or daily. Optionally scoped to one fingerprint. Use this to spot regressions ("when did this bug start firing?") or post-deploy spikes ("did the deploy at 14:00 break something?").
Returns a series of { bucket, count } rows. The bucket field is an ISO timestamp aligned to the start of the interval. Buckets with no errors are omitted (sparse series); the agent should treat missing buckets as zero.
Examples:
- "error rate over the last week" → period="7d" (returns hourly buckets)
- "did errors spike after yesterday's deploy" → period="2d", interval="hour"
- "is this specific fingerprint getting worse" → fingerprint="<hex>", period="30d"
- "yearly error trend" → period="365d", interval="day"
Limitations: interval defaults to "hour" for periods ≤ 7 days, "day" otherwise. Override only if the default produces too few or too many buckets for the question. No fingerprint filter returns the total error rate across all bugs.
Pairs with: `errors.groups` (find which fingerprint is worth charting); `traffic.timeseries` (compare error count to traffic count to see if the rate is real or just a traffic surge); `traffic.compare` (week-over-week or before-after-deploy comparison).
Connector