Model-switch consent can no longer fire twice

/model can no longer apply a second model change or print a duplicate notice.

You'll notice Improvements

JSON All of v2.1.248

You'll noticeTier: how much it should matter to you

3Useful: my rating, 1 to 5

1Signal: worth watching, 1 to 5

ModelsArea: what it touches

ImprovementsKind: in v2.1.248, 27 Aug 26

ImprovementsSection of the release

What

A stale consent callback from /model can no longer apply a second model change or print a duplicate "Kept model as" notice. The picker now tracks whether it has already been answered and returns early if so.

Details

Both the /model command and the model-switch component carry a generation counter and an already-handled flag, checked before the model change is applied.
The user-facing strings moved into shared constants with no wording change.

Evidence

Kept model as

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Read from

Names in the bundle/model

Since it was published

The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.

Confirmed since 10 Sep 2026 Anthropic's documentation has since written up /model, on All settings. Cap the [effort level](/docs/en/model-config#adjust-effort-level) a session can use, leaving lower levels available. Any higher level runs at the cap instead, including one from `/effort`, the `/model` picker, `--effort`, [`CLAUDE_CODE_EFF… settings-reference see the edit

Added since 10 Sep 2026 A small documentation edit on Agent SDK reference - TypeScript touched a line naming /model after this was published. `effortLevel` accepts an [effort level](/docs/en/model-config#adjust-effort-level) name. It also accepts `"ultracode"`, which requests `xhigh` effort with [ultracode](/docs/en/workflows#let-claude-decide-with-ultracode) on. `applyFlagSetti… agent-sdk/typescript see the edit

How sure we are

Two sources agreeTwo things we can check say the same as this entry.

Anthropic's documentation agreesA small documentation edit on Agent SDK reference - TypeScript touched a line naming /model after this was published.

Anthropic's release notes agreeFixed model names in /model and fast-mode switch notices to render as code, so suffixes like [1m] display literally instead of as a link

See this entry in the whole of v2.1.248 →

The build it came inv2.1.248

27 Aug 2026 · 876 entries, this one is #529.

Use it now64
You'll notice420
Nothing to try yet95
Under the hood297

Either side of it

v2.1.247Older
v2.1.250Newer

Open the release →

Names in this entry

slash/model
Switch the AI model and save it as your default for new sessions. For models that support it, use left/right arrows to adjust effort level. With no argument, opens a picker; press s on a row to switch for the current session only. See when Claude Code asks you to confirm the switch. Once you confirm the switch, if Claude Code asks, Claude Code applies the change without waiting for the current response to finish. Before v2.1.242, Claude Code decided from a feature flag it fetched from Anthropic whether to run the command mid-turn or queue it until the turn finished, and always queued it in a session that doesn't fetch feature flags, such as on a third-party provider. Also available in non-interactive mode (-p) with a model argument instead of the picker, where it applies to the current session only and isn't saved as your default; requires Claude Code v2.1.205 or later

Anthropic's note

Upstream's own release notes for v2.1.248 name something this entry names, so the two are probably about the same change. Probably: the pairing is made on a shared name rather than on the words around it.

Fixed model names in /model and fast-mode switch notices to render as code, so suffixes like [1m] display literally instead of as a link

Is this right?