We are a paying customer and have recently seen a significant increase in our usage. As a result, we are frequently encountering 429 errors, especially for our connected Google accounts.
I’ve read the rate limit documentation (Nylas API and provider rate limits | Docs), and I understand that Google uses a quota-based system (e.g., 100 units per send). We are trying to build a robust queueing system to manage this.
My main question is: Does Nylas perform any background API calls (e.g., syncing new emails) that would consume our Google API quota?
We’re trying to build a local rate limiter, but it’s difficult to predict the total quota usage if there are “hidden” requests from Nylas. Any guidance or best practices on how to reliably manage Google’s quota when sending emails at scale would be greatly appreciated.
The error code I received is like this: {‘error’: {‘message’: ‘Activity limit reached’, ‘provider_error’: {‘error’: {‘code’: 429, ‘message’: ‘User-rate limit exceeded. Retry after 2026-01-08T09:26:53.594Z (Mail sending)’}}, ‘type’: ‘quota_exceeded_error’}, ‘request_id’: ‘3305114997-9753c430-2599-4bcc-8f25-9165b071227a’}, does it mean that I can cool grantid to 2026-01-08T09:26:53.594Z before sending
The short answer: Yes, Nylas does make background sync calls. The good news is that background sync operations consume a negligible fraction (~0.5%) of your available quota. Your rate limiter primarily needs to manage send operations at approximately 2 sends per second per user to stay within quota.
That’s correct. We recommend following the Retry-After header. To avoid rate limits when fetching data, we suggest listening to our webhooks and maintaining a local cache so you don’t need to fetch from the provider each time. Since send operations consume the most units, this is the area you’ll need to monitor most closely.
Thank you very much for your help. I asked through ask ai that the reretry header is not supported. Do you mean that I can parse the reretry in the nylas api response header like Microsoft’s header to obtain the cooldown time in seconds
No, Google does not return a standard Retry-After HTTP header. Instead, Google embeds the retry timestamp in the error message body. Nylas parses this timestamp from the error body.
Since Google’s retry information is located in the error body rather than the header:
Check for the Retry-After header in 429 responses from Nylas. We extract and forward it when possible.
If no header is present, fall back to a 1-second backoff. Google’s quota resets every second.
Add jitter. Nylas adds up to 30 seconds of internal jitter to prevent a thundering herd.