1-based attempt number that is about to be retried (i.e. the one that just failed).
First 500 bytes of the failing response body (best-effort).
Milliseconds the client is about to sleep before the next attempt.
HTTP status that triggered the retry.
Fully-qualified request URL.
Diagnostic payload passed to ResilientHttpClientOptions.onRetry once per retry attempt. Useful for emitting a structured log line.