A 502, 503 or 504 from the LiteLLM proxy, or a dropped connection, is
retried after 5, 15 and 45 seconds before the call fails. Twice on
2026-10-07 a short burst of 502s stopped work outright: the integration
tier at 16:39 and an e2e conversation at 20:43, where the item waited on
the operator after one refused call.
Not retried: a 500 (it may be the request's fault), a timeout (it already
had its request_timeout_s), or a budget refusal. Rate limits keep their
single 20-second retry. The time spent waiting is reported with the rate
limit's (last_rate_limit_wait_s), so it isn't counted as the model's.
Tests: an outage waited out, one that outlasts the backoff, a dropped
connection, a 500 and a timeout not retried, a budget refusal not waited
on. The offline agent in test_agent_build skips the backoff (its proxy
doesn't exist).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE
dongarandClaude Opus 5.5