Claude Code makes Opus 5 the default Opus model and narrows fast mode to it

Claude Code 2.1.219 (July 24, 2026) makes Claude Opus 5 the default Opus model. It ships with a 1M-token context window, and fast mode on it prices at $10/$50 per Mtok (input/output).

The release also narrows which models fast mode covers. Opus 4.7 is removed from fast mode entirely; only Opus 5 and Opus 4.8 support /fast now.

/fast on

The /model picker changed to match: it now highlights only the newest model's name, so the highlight marks the new release instead of an arbitrary subset of the list. A separate fix in the same release stops the picker from showing the merged Opus row as plain "Opus" — it now reads "Opus (1M context)" — and clears up a stale-cache bug that showed "Requires usage credits" on the Fable row for plans that already include it.

What this means

If you had /fast toggled on with Opus 4.7, that stopped working on 2.1.219 — switch to Opus 5 or Opus 4.8 to keep fast mode. Run claude --version to confirm you're on 2.1.219 or later, and see the Claude Code sheet for the current model and fast-mode surface.