Returns the number of calls per agent for each time bucket in the window, for charting request volume. Calls with no agent are not counted. Agents named in agents appear in every bucket, with 0 where they had no calls. For one count per agent over the whole window, use GET /v2/api/sources/metrics/ai/call-count-metrics-by-agents.

Bucket size by period: HOUR 5 minutes, EIGHT_HOURS 30 minutes, TWENTY_FOUR_HOURS 2 hours, SEVEN_DAYS 12 hours, THIRTY_DAYS 1 day, NINETY_DAYS 1 week, SIX_MONTHS and TWELVE_MONTHS 1 calendar month. Buckets are cut in UTC. Monthly buckets start at midnight UTC on the first of each month; shorter buckets start at the beginning of the window, which is the time of the request minus the period. With a custom startDate and endDate the range is not split evenly: the response has ten buckets, the first covers the whole range and the other nine are empty. Buckets are listed oldest first.