Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
I understand that you would like to programmatically get the Maximum Quota limit of Azure Traffic Manager.
As of today, this is not feasible.
The same applies to other Non-regional Resources such as AFD and CDN.
If you feel this feature is required, you may vote in Azure Feedback Hub forum requesting this feature.
All the feedback shared in these forums are monitored and reviewed by the Microsoft engineering teams responsible for building Azure
https://feedback.azure.com/d365community/forum/8ae9bf04-8326-ec11-b6e6-000d3a4f0789
I will also share this feedback internally to our Azure Front Door Product Group team for further tracking.
Kindly let us know if this helps or you need further assistance on this issue.
Thanks,
Kapil
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