Claude Code 2.1.81 adds bare mode for scripted calls and channels permission relay
New Features
Bare Mode for Scripted Calls
The new --bare flag streamlines scripted -p calls by skipping hooks, LSP, plugin sync, and skill directory walks. This mode requires either ANTHROPIC_API_KEY or an apiKeyHelper via --settings, with OAuth and keychain authentication disabled and auto-memory fully disabled. This is useful for CI/CD pipelines and automation scenarios that need minimal overhead.
Channels Permission Relay
A new --channels permission relay feature allows channel servers declaring the permission capability to forward tool approval prompts to your phone, enabling mobile approval workflows during remote code execution.
Major Bug Fixes
- OAuth reauthentication: Fixed multiple concurrent Claude Code sessions requiring repeated reauthentication when one session refreshes its OAuth token
- Voice mode stability: Resolved silent retry failures, audio recovery on WebSocket drops, and misleading network error messages
- Session resumption: Sessions that were in a worktree now correctly switch back to that worktree on resume
- Header compatibility: Fixed
CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETASnot suppressing the structured-outputs beta header, which caused 400 errors on proxy gateways forwarding to Vertex/Bedrock
Additional Improvements
- Enhanced MCP read/search tool calls to collapse into summary lines with Ctrl+O expansion
- Improved plugin freshness—ref-tracked plugins now re-clone on every load
- Updated MCP OAuth to support Client ID Metadata Document (CIMD / SEP-991)
- Changed plan mode to hide "clear context" option by default
- Disabled line-by-line response streaming on Windows (including WSL) to fix rendering issues
- Fixed Windows PATH inheritance for Bash tool when using Git Bash
- 15+ additional targeted fixes for edge cases, race conditions, and UI responsiveness