The scheduling API has been restricted for a few days now (I checked). However, the search API is public and you an write a script to poll it to check for slots availability. But you still need to rush and book it.
I feel given the vaccine shortage, this system is very flawed for a country like India. Curious to know what a better system design could be to address this issue.
https://twitter.com/saurabhj/status/1389840816026230788?s=21
Rushing to book a slot is bad design and a captcha to block scripts is just a lazy way to think about it.