Claude Code v2.1.63 Release Notes

The Claude Code team has released version 2.1.63, bringing significant performance improvements and new productivity features for power users. This release focuses heavily on fixing memory leaks and improving long-running session stability, while also introducing valuable new tools.

What’s New

New Slash Commands

Two powerful new bundled slash commands have been added:

/simplify - Streamline complex code or explanations
/batch - Process multiple items efficiently

HTTP Hooks

A major new feature allows you to POST JSON to URLs and receive JSON responses instead of running shell commands. This opens up powerful integration possibilities with web APIs and services.

Enhanced Model Management

The /model command now shows the currently active model directly in the slash command menu, making it easier to track which model you’re using.

MCP Server Control

Added ENABLE_CLAUDEAI_MCP_SERVERS=false environment variable to opt out from making claude.ai MCP servers available, giving you more control over your setup.

Improved Copy Functionality

The /copy command now includes an “Always copy full response” option. When selected, future /copy commands will skip the picker and copy the entire response directly.

VSCode Enhancements

Remote sessions now properly appear in conversation history
Added session rename and remove actions to the sessions list

Git Worktree Support

Project configurations and auto memory are now shared across git worktrees of the same repository, improving workflow consistency.

Major Performance Fixes

This release addresses numerous memory leaks that could impact long-running sessions:

Fixed listener leaks in bridge polling and MCP OAuth flows
Resolved memory leaks in bash command prefix cache and git root detection
Fixed WebSocket listener leaks on transport reconnect
Improved memory usage in long sessions with subagents
Fixed MCP tool/resource cache leaks on server reconnect
Resolved race conditions in REPL bridge message ordering

Bug Fixes

Local slash command output now correctly appears as system messages
Fixed /clear not resetting cached skills
Improved file count cache to respect glob ignore patterns
Added manual URL paste fallback for MCP OAuth authentication

How to Update

To update to Claude Code v2.1.63:

Check for updates in your Claude Code installation
Follow the standard update process for your platform
Restart your development environment to ensure all changes take effect