New — the By Model report See exactly which Claude models are driving your costs. By Model breaks your usage down per model, month by month — input, output, cache, and total tokens alongside the dollar cost — so you can spot when a pricier model is quietly running up the bill, then adjust. Full CSV export included. By Model is a Costwell Pro feature.

Your history, kept. Claude Code deletes its own session logs after about 30 days by default — so older usage quietly drops out of most trackers. Version 1.0.3 makes sure it doesn't drop out of Costwell. • Retention heads-up — Costwell now notices when Claude Code is set to clear your logs and shows you the one-line change to keep more history, before it's gone. • Complete all-time totals (opt-in) — turn on "Include cleaned-up sessions in totals" and Costwell folds already-removed sessions back into your lifetime cost and usage from its local index, re-priced at current rates, so your numbers stop shrinking as files age out. As always, everything stays on your Mac. Nothing is uploaded.

Day-one pricing for Claude Fable 5 • Adds Anthropic's new Claude Fable 5 (and Claude Mythos 5) at the official $10/$50 per-million-token rates, including correct prompt-cache write and read pricing. • Fixes Fable 5 sessions being priced at Sonnet rates — costs were under-reported by about 3.3×. Totals now match Anthropic's published pricing.

Costwell now supports Claude Opus 4.8. • Usage, cost, and burn rate for Claude Opus 4.8 — Anthropic's latest model — are now tracked at the correct rates, including its full 1M-token context window. • Your daily, monthly, and per-session totals stay accurate now that Opus 4.8 is part of your usage.