Claude Code v2.1.86 Release Notes

Claude Code v2.1.86 brings major performance improvements, VCS integration enhancements, and critical bug fixes for power users.

March 28, 2026 • 10 min read • By ClaudeWorld

Claude Code v2.1.86 delivers significant improvements to performance, version control integration, and overall stability. This release focuses on addressing critical bugs while introducing smart optimizations that enhance the developer experience for power users.

What’s New

Enhanced API and Session Management

  • New session tracking: Added X-Claude-Code-Session-Id header to API requests, enabling proxies to aggregate requests by session without parsing request bodies
  • Improved VCS support: Added .jj and .sl to VCS directory exclusion lists, preventing Grep and file autocomplete from descending into Jujutsu or Sapling metadata directories

Performance and Memory Optimizations

  • Reduced memory usage: Fixed memory growth in long sessions by optimizing markdown/highlight render caches
  • Faster startups: Reduced startup event-loop stalls when many claude.ai MCP connectors are configured (macOS keychain cache extended from 5s to 30s)
  • Token efficiency: Reduced token overhead when mentioning files with @ — raw string content no longer JSON-escaped
  • Better cache hits: Improved prompt cache hit rate for Bedrock, Vertex, and Foundry users by removing dynamic content from tool descriptions

Critical Bug Fixes

  • Resume functionality: Fixed --resume failing with “tool_use ids were found without tool_result blocks” on sessions created before v2.1.85
  • File operations: Resolved Write/Edit/Read failures on files outside the project root when conditional skills or rules are configured
  • Config stability: Fixed unnecessary config disk writes that could cause performance issues and config corruption on Windows
  • Memory safety: Fixed potential out-of-memory crash when using /feedback on very long sessions

VSCode Extension Improvements

  • Fixed extension incorrectly showing “Not responding” during long-running operations
  • Resolved issue where Max plan users were defaulted to Sonnet after OAuth token refresh

User Interface Enhancements

  • Interactive memories: Memory filenames in “Saved N memories” notices now highlight on hover and open on click
  • Organized skills: /skills menu now sorts alphabetically for easier scanning, with descriptions capped at 250 characters
  • Clearer messaging: Auto mode now shows “unavailable for your plan” when disabled by plan restrictions
  • Better scrolling: Fixed scroll behavior to follow new messages after manual scroll or selection

How to Update

To update to Claude Code v2.1.86:

  1. Automatic updates: If you have automatic updates enabled, the new version will be downloaded and installed automatically
  2. Manual update: Run claude-code --update from your terminal
  3. Fresh installation: Download the latest version from the official release page

After updating, restart any active Claude Code sessions to ensure all improvements take effect.