Claude-Code v2.1.216: Filesystem isolation, performance, and bug fixes
Claude-Code v2.1.216 introduces a new setting to disable filesystem isolation, enhancing flexibility for developers. This release also addresses critical performance regressions in long sessions and resolves numerous bugs affecting command execution, session resumes, and cross-platform compatibility. These fixes are crucial for maintaining stable and efficient development workflows for users interacting with Claude for code-related tasks.
- →New option to disable filesystem isolation
- →Resolved quadratic cost slowdown in long sessions
- →Fixed auto mode errors after OAuth token rotation
- →Improved AskUserQuestion command behavior
- →Corrected session resume issues after idle periods
Features (1) ›
- New option to disable filesystem isolation
A new `sandbox.filesystem.disabled` setting is now available, allowing users to skip filesystem isolation while retaining network egress control. This provides more flexibility for workflows that require direct filesystem access.
Fixes (5) ›
- Resolved quadratic cost slowdown in long sessions
Fixed a performance issue where message normalization cost grew quadratically with the number of turns in long sessions. This caused multi-second stalls and slow session resumes.
- Fixed auto mode errors after OAuth token rotation
Addressed an issue where auto mode would deny commands with "HTTP 401" classifier errors after the OAuth token expired or rotated mid-session.
- Improved AskUserQuestion command behavior
Fixed AskUserQuestion commands to provide neutral wording when Claude is instructed to wait or explain first, preventing unnecessary continuation prompts.
- Corrected session resume issues after idle periods
Resolved a bug where Claude Code on the web would re-ask questions and drop answers after sessions sat idle for a few minutes.
- Fixed various @-mention and session resume glitches
Addressed issues with @-mentions failing to attach files, statusline running twice on resume, and resume-pickers hanging on failure. Resumed background agent sessions now correctly restore their prompt and tool restrictions.
https://github.com/anthropics/claude-code/releases/tag/v2.1.216
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