Archive services are free, independently run, and offer no uptime guarantee. They are sometimes slow and occasionally offline.
How Subdex responds
Throttling. Two concurrent requests maximum, always. This is not configurable, and there is no proxy rotation.
Backoff. When a provider signals rate limiting, requests pause and resume rather than retrying immediately.
No retry on rejection. A query the archive rejected as invalid is not retried, because retrying an invalid query only consumes the rate limit.
Partial results. If some requests succeed and others fail, what arrived is shown and marked partial, with the reason listed.
Checking status
The status page checks the archive sources when you ask it to. It does not poll them on a schedule — that would cost a free service bandwidth for no research benefit.
What still works offline
Saved research, the workspace, exports of already-loaded data and every informational page. Only new searches need the network.