We don't currently limit or throttle web API access (we might in the future). What we currently do is we occasionally flag extremely high API usage and work with the developers to use the API more smartly -- which is usually as simple as caching things for a while rather than hammering the servers.
For today task I've put 2 seconds breaks between requests
Do you mean you're doing something continually (non-stop, forever) and there are 2 second breaks between this activity? If that's what you mean, then you've got a design problem. You should be caching data, and requesting data strategically.
Or do you mean you're doing "things" (short tasks that's not a continuous, never-ending process)? If so, then there's no need to do any delay between requests.
Does that make sense?