I am wondering if I have AWS Cross Account Observability setup, and I make getMetricData api calls from the monitoring account X but getting metrics for source account Y which account gets billed for those api calls?
The AWS pricing page makes no mention of it.
After testing I found out that the monitoring account gets billed for any getMetricData api calls made from it even if they are gathering metrics on other accounts. The other, source, accounts don't get charged anything at all.