Claude Code v2.1.191: /rewind, CPU fixes, MCP reliability improvements
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.
/voicenow explains the organizational restriction instead of showing a generic message./loginURL 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. /permissionsRecently-denied tab: approving a denial now persists on close.- Managed settings:
forceRemoteSettingsRefreshnow works via MDM or file policy, and the fetch sendsCache-Control: no-cacheto 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.
📖 Read the full source: GitHub Claude-Code
👀 See Also
The State of Open Source AI: Parity Reached, Production Gap Remains
Mozilla's 2026 report finds open-weight models at parity with closed on coding and general knowledge, with 50x inference cost drop to $0.40/M tokens. But only 51% of open-model teams reach production vs 63% for closed.
Claude Code v2.1.77 Release: Token Limits, Sandbox Controls, and Bug Fixes
Claude Code v2.1.77 increases default maximum output token limits for Claude Opus 4.6 to 64k tokens and adds an allowRead sandbox filesystem setting. The release includes over 30 fixes for issues ranging from memory management to terminal UI behavior.
Simple Self-Distillation Method Improves LLM Code Generation
Researchers show that fine-tuning LLMs on their own sampled outputs (simple self-distillation) improves code generation performance, boosting Qwen3-30B-Instruct from 42.4% to 55.3% pass@1 on LiveCodeBench v6.
Claude-Code v2.1.33: Enhancing Automation with Precision
The latest release of Claude-Code v2.1.33 introduces key features that further revolutionize AI coding agents, boosting both efficiency and accuracy.