claudekit / updates / claude-code-2-1-191
[ PATCH · ]

Claude Code 2.1.191

`/rewind` now supports resuming a conversation from before `/clear` was run. CPU usage during streaming responses drops by ~37% by coalescing text updates to 100ms, and sandbox network hosts you allow with "Yes" are remembered for the rest of the session instead of re-prompting on every connection. MCP capability discovery and OAuth now retry transient network errors, and a batch of bug fixes lands: stopped background agents no longer resurrect, and hooks with comma-separated matchers (e.g. "Bash,PowerShell") no longer silently fail to fire.

Claude Code
Official announcement →

This article is a summary based on official documentation.

What changed

Claude Code 2.1.191 extends /rewind to restore from before /clear and brings performance work that cuts CPU during streaming and memory growth in long sessions. Alongside reliability improvements — transient-error retries for MCP connections and remembered sandbox network permissions — it cleans up bugs across background agents, hooks, permissions, and terminal rendering.

New features

  • /rewind support for resuming from before /clear

    Once /clear was run, there was no way back to the prior conversation, so an accidental clear meant losing that context. /rewind can now resume a conversation from before /clear was run.

Key improvements

  • Sandbox network permission dialog remembers allowed hosts

    Hosts you allowed with “Yes” still re-prompted on every connection. They are now remembered for the rest of the session instead of re-prompting each time.

  • MCP server reliability — capability discovery retries

    Capability discovery (tools/list, prompts/list, resources/list) dropped on a single transient network error. It now retries transient network errors with short backoff.

  • MCP OAuth retries and headless support

    MCP OAuth discovery and token requests stalled on transient network errors, and headless environments got stuck trying to open a browser popup. Discovery and token requests now retry once after transient network errors, and headless environments skip the browser popup and go straight to the paste-the-URL prompt.

  • Clearer MCP error messages

    An MCP HTTP 404 error gave little to go on. It now shows the URL and points to your MCP config.

  • vim mode prompt-history search hint

    Searching prompt history with NORMAL-mode / in vim mode gave no cue for reaching slash commands. It now hints how to get to slash commands.

  • ~37% less CPU during streaming responses

    Streaming responses re-rendered on every text change, driving high CPU. Coalescing text updates to 100ms reduces CPU usage during streaming responses by ~37%.

  • Reduced long-session memory growth

    The terminal output cache accumulated as sessions ran long, growing memory over time. Long-session memory growth from that cache is now reduced.

Bug fixes

Background agents

  • Background agents resurrecting after being stopped — stopping an agent from the tasks panel is now permanent.
  • claude agents sending builtin slash commands like /usage to background sessions as prompt text — it now shows a hint instead of sending the command as text.
  • claude agents job rows showing full filesystem paths for pasted images — they now show the [Image #N] placeholder.

Permissions & settings

  • Hooks with comma-separated matchers (e.g. "Bash,PowerShell") silently never firing — fixed.
  • /permissions Recently-denied tab discarding an approved denial on close — approving a denial now persists instead of being silently discarded.
  • Managed settings forceRemoteSettingsRefresh not taking effect when set via MDM or file policy — fixed; the fetch now sends Cache-Control: no-cache to prevent proxies from serving stale responses.
  • /voice showing a generic “not available” message when disabled by an organization’s policy — it now explains the restriction.

Terminal & display

  • Scroll position jumping to the bottom while reading earlier output during a streaming response — fixed.
  • /login URL opening truncated in Windows Terminal when it wraps across lines — fixed.
  • Cmd+click on links not working in fullscreen mode for Ghostty over ssh/tmux — fixed.
  • The agent panel jumping by one row when scrolling the roster past the overflow cap — fixed.
  • The welcome splash art overflowing the default 80×24 macOS Terminal window — fixed.

Notes

  • The streaming CPU win comes from coalescing text updates to 100ms — it batches the render cadence; response speed itself is unchanged.
  • Re-check comma-separated matcher hooks — hooks with matchers like "Bash,PowerShell" that silently never fired will start running after the upgrade. Confirm they fire as intended.
  • Sandbox host approvals are session-scoped — an allowed host is remembered only for that session. Starting a new session prompts again.