Rate Limits
The API has two separate rate limits. These dictate how many calls can be made to the server within a given time. Enforcing rate limits prevents a single app or user from overwhelming the server. The response codes will tell you if you've hit your limit. Your application should be looking for these and if it encounters a rate limit status code, it should back off until it hits the reset time. Ignoring these codes may cause your access to be disabled.
User Limit
Each user is limited to 120 calls per hour. This should be very sufficient for most users as the average user only makes changes to their list periodically. To ensure the user stays within this limit, make use of the send method for batching requests.
API Key Limit
Each application is limited to 1000 calls per hour. If your application grows to be popular and requires to be whitelisted, please contact me. If you are adding RIL support to an existing application with a large user base and think you might hit this limit right off the bat, please contact me.