Hi @HIR
We have simplified this now - we have two types of APIs (Trading & Data APIs). Trading APIs are free for all and Data APIs are INR 499 per month.
As usual, we charge competitively to cover for our infrastructure investments & avoid misuse. We understand many users have already their integrations for marketfeed and historical data, so they have a choice to integrate just the trading APIs for free (no cost). While those who are getting started with building their own web-sockets for data it is INR 499, possibly also for those who want to switch to our market-feed.
Hope this helps.