Get Message IDs for Campaignget https://a.klaviyo.com/api/campaigns/{id}/relationships/campaign-messagesReturns the IDs of all messages associated with the given campaign.Rate limits:Burst: 10/sSteady: 150/m Scopes: campaigns:readPath ParamsidstringrequiredHeadersrevisionstringrequiredDefaults to 2025-01-15API endpoint revision (format: YYYY-MM-DD[.suffix])Responses 200Success 4XXClient Error 5XXServer ErrorUpdated over 1 year ago