Claude Code 2.1.191: /rewind, CPU fix, MCP retries

Anthropic released Claude Code v2.1.191 with a handful of fixes and improvements that directly affect daily agent usage. Notable additions include /rewind support, a ~37% CPU reduction during streaming, and several MCP reliability enhancements.

New command: /rewind

/rewind now lets you resume a conversation from before a /clear was run. If you accidentally wiped context, you can restore the prior session without restarting from scratch.

CPU usage and memory

Streaming response CPU usage is reduced by ~37% via coalescing text updates to a 100ms interval. Long-session memory growth from terminal output cache has also been reduced.

Agent fixes

Stopping an agent from the tasks panel is now permanent — background agents no longer resurrect after being stopped.
Builtin slash commands (like /usage) sent to background sessions now show a hint instead of being passed as prompt text.
Job rows for pasted images now display [Image #N] placeholder instead of full filesystem paths.

MCP improvements

Capability discovery (tools/list, prompts/list, resources/list) now retries on transient network errors with short backoff.
MCP OAuth discovery and token requests retry once after transient errors; headless environments skip the browser popup and go straight to the paste-the-URL prompt.
HTTP 404 errors now show the URL and point to your MCP config.

Other fixes

Scroll position no longer jumps to the bottom while reading earlier output during a streaming response.
/voice now explains the organizational restriction instead of showing a generic message.
/login URL no longer gets truncated in Windows Terminal when it wraps across lines.
Cmd+click on links in fullscreen mode works again for Ghostty over ssh/tmux.
Hooks with comma-separated matchers (e.g., "Bash,PowerShell") now fire correctly.
/permissions Recently-denied tab: approving a denial now persists on close.
Managed settings: forceRemoteSettingsRefresh now works via MDM or file policy, and the fetch sends Cache-Control: no-cache to prevent stale proxy responses.
Sandbox network permission dialog now remembers hosts allowed with "Yes" for the session.
Vim mode prompt-history search (NORMAL /) hints how to reach slash commands.