Under the hood
Claude Code now tracks token-budget usage per conversation and logs when it crosses key thresholds
What
Claude Code now has a tracker that follows cumulative token usage separately for the main conversation and for subagents (helper conversations spun off from the main one). It supports "rolling over" unused budget and re-anchoring the tracker, and it logs an event each time the remaining budget crosses 75%, 50%, 25%, 10%, or 0% of the total, along with how many rollovers have happened and how long since the tracker was last anchored.
Why
This gives finer-grained visibility into how token budgets are consumed over a session, which can help identify when context is running low before it becomes a problem.