This agent runs 30-minute sessions, but the dev shipped without
ttl, relying on the provider default. Anthropic's default cache
TTL is 5 minutes — so this code re-writes its cache up to 6× per
session instead of once, quietly overspending on every run.
Fix the cache_control to pass ttl: "1h" explicitly so the cache
survives the whole session (and so the TTL is pinned regardless of
any future provider default changes).
Expected output:
ttl: 1h
The break is on line 5 — but read the whole snippet first.