What are the restrictions on usage of real-time protocols?

Real-time streaming protocols (WebSocket and FIX) are restricted by the data types available and the maximum number of connections/sessions that can be established concurrently. More information about the specific limits on each plan you can find on our Pricing page [1] and API Documentation [2]

Reference:

[1] https://www.coinapi.io/Pricing 

[2] https://docs.coinapi.io/#limits-2