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Quotas

Every API request is measured for CPU usage and requests return 429 once a daily limit is reached. This is just an informal safeguard against excessive API usage and internal logical errors (say, in case an API gets into an infinite loop of spawning requests through batching).

Limits are on a user-by-user basis, so clients are not penalized for having many users.

The current limit is about a billion megacycles (Mcycles). Downloading all Items and Vocabs (including all related sentences, top mnemonics, and decomps) for a relatively large account in one large batch takes in the neighborhood of a few million Mcycles.