It depends on what you want to use SQL Agent for. Most of the SQL Agent jobs I've seen in the past have been planning backups or SSIS packages. None of these are related to SQL Azure. Azure SQL backup planning is done through the Azure portal, and SSIS is not used.
Other scheduled maintenance tasks that you might want to complete, such as rebuilding indexes or moving data around, must be manually deployed. I suggest you create a small application using the ASP MVC Web API, which has scripts that you want to execute. You can run it pretty much free, like the Azure site, if you need to. Then call this service from an external scheduler. Keen's answer to your question provides some options. Personally, I use setcronjob , which meets our needs and costs me only $ 10 a year.
Perhaps provide specific examples of what you want to plan in your question so that you can provide answers to specific questions.
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