User analysis says Claude Code's prompt cache TTL dropped from 1 hour to 5 minutes in early March

An analysis of 119,866 API calls from January 11 to April 11, 2026 claimed the cache TTL silently changed from 1 hour to 5 minutes around early March, raising cache creation costs 20 to 32% and quota use. The Hacker News thread drew 552 points and 420 comments.

Who is affected:

Claude Code subscribers whose quota drained faster from March 2026.

What to do:

No action needed. See Anthropic's April 23 postmortem.