The Publish to Azure Search publisher will post documents to an Azure Search index through https://<server>/indexes/<index>/docs/index?api-version=<apiVersion> as described by Azure Search in the Bulk API.
Some of the features of the Publish to Azure Search publisher include:
The publisher itself is subjected to the Azure Search Service limitations.:
More information at https://docs.microsoft.com/en-us/azure/search/search-limits-quotas-capacity and https://docs.microsoft.com/en-us/azure/search/search-create-index-portal