Claude Code v2.1.210: worktree isolation bug fix and safer permission-rule warnings
Claude Code 2.1.210 fixes worktree-isolated subagents being able to run git-mutating commands against the main repo checkout instead of their own worktree.
What it is
A release of Anthropic's Claude Code CLI, the terminal-based coding agent.
What it does
It fixes isolation: 'worktree' subagents leaking git-mutating commands into the main checkout, adds a startup warning steering users toward Edit(path)/Read(path) instead of Write(path)/NotebookEdit(path)/Glob(path) permission rules, adds a live elapsed-time counter on long-running tool calls, and stops the ultracode keyword from firing on non-human input like webhook payloads.
Why it matters
The worktree isolation fix matters for anyone relying on isolated subagent worktrees to sandbox risky git operations away from a real repository, since the bug meant that isolation guarantee could silently fail.
How to use it
Update to Claude Code v2.1.210 or later; review any permission rules using Write/NotebookEdit/Glob path matching and switch to Edit/Read equivalents.