Constant POLL_TICK_TIMEOUT 

const POLL_TICK_TIMEOUT: Duration;

The most one poll tick – the claim’s up to two sequential HTTP round trips, then the local decision – may take before the tick is abandoned.

A backstop on top of the client’s own budget, not a substitute for it: didbot_http::client falls back to a client with no timeout at all if its builder ever fails to construct one, and this is what still bounds a tick if that happens. Thirty seconds is triple didbot_http::DEFAULT_TIMEOUT, which is the most either HTTP call normally takes.