When trying to get a list of questions for the C# tag, the total field was missing. Tried with Python tag and the total was included.
/2.2/questions?order=ASC&sort=creation&site=stackoverflow.com&pagesize=1&page=1&tagged=c#
/2.2/questions?order=ASC&sort=creation&site=stackoverflow.com&pagesize=1&page=1&tagged=python
The URL needs to be URL-encoded such that c# becomes c%23. Then total appears in the results.
https://api.stackexchange.com/2.2/questions?order=ASC&sort=creation&site=stackoverflow.com&pagesize=1&page=1&tagged=c%23&filter=!9_bDE.BDp
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