can you change the status line so I can see the `Usage credits` of the month?

Done — ~/.claude/statusline-command.sh now shows month-to-date usage credits:
With a spend cap configured it renders credits $1,034.10/$2,000.00 (52%). Your account has monthly_limit: null (unlimited), so only the spent amount shows. Old script backed up at statusline-command.sh.bak; settings.json already pointed here, so no config change was needed.
Where the number comes from: the statusline JSON Claude Code feeds to the script only carries rate_limits.five_hour / seven_day — no credits field. So the script reads Claude Code's own cached /api/oauth/usage payload from ~/.claude.json (.cachedUsageUtilization.utilization.spend, falling back to .extra_usage for the older schema). No network call, no token handling, ~15 ms per render.
The one caveat: that cache is refreshed only when Claude Code fetches usage (opening /usage, /status, /usage-credits), not on a timer — so it can go stale. Rather than hide that, the script appends the age once it's over 30 minutes old (credits $1,034.10 (2h ago)). Run /usage to force a refresh. Restart or /statusline reload to see it in this session.