GitLab

Prevents 429 rate-limit retry storms and reduces upstream correlation risk
for Anthropic usage API queries.

Three changes:
1. Negative caching (1 min TTL) — 429/error responses are now cached,
   preventing every subsequent page load from re-triggering failed API calls.
2. singleflight dedup — concurrent requests for the same account are
   collapsed into a single upstream call, preventing cache stampede.
3. Random jitter (0–800 ms) — staggers multi-account cache-miss bursts so
   requests from different accounts don't hit upstream simultaneously with
   identical TLS fingerprints, reducing anti-abuse correlation risk.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>