Hello,
Thanks for reaching out. The 1 QPS limit is applied to the whole service, so if GenerateForecastMetrics is the only method of the service being called, then the limit will simply be 1 QPS. This method is not a GET, so the 1000 limit does not apply.
Additionally it is not technically an
operation, so the 15,000 basic access operation limit does not apply here.
Regards,
Matt
Google Ads API Team

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