/ Claude Code v2.1.126

The release notes / onboarding-version comparators were rewritten as new functions (OK5, N55, MI5) replacing the old (wK5, h55, jI5). This is a pure version-string churn artifact: each function compares the user's last-seen version to the constant 2.1.126 instead of 2.1.124. No behavior change.
This release does not bump any models, change any commands or flags, add any settings, or alter permission rules. If you only care about user-facing surface area, the two notable changes are persistent /effort and the removal of the Read-tool malware reminder.

The build it came inv2.1.126

30 Apr 2026 · 5 entries, this one is #5.

Either side of it

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Names in this entry

slash/effort
Set the effort level: low to xhigh, max, ultracode, or auto; status prints it. max and ultracode are session-only; the ultracode key persists. Run it while Claude is responding and, once you confirm the cache warning, if Claude Code shows one, Claude Code applies the new level to the next request in that turn. 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. Works in -p

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