Claude Code 2.1.90: Rate Limit Fixes, Performance Gains

TL;DR

• Fixed infinite loop crash when hitting rate limits — dialog no longer auto-opens repeatedly
• Major performance improvements: eliminated quadratic slowdowns in SSE transport and SDK transcript writes
• Fixed `--resume` cache miss regression affecting users with deferred tools and MCP servers
• Hardened PowerShell permission checks against background job and debugger bypasses

New

• /powerup — Interactive lessons with animated demos teaching Claude Code features
• CLAUDE_CODE_PLUGIN_KEEP_MARKETPLACE_ON_FAILURE — Env var to preserve marketplace cache when `git pull` fails, critical for offline environments
• .husky protected — Added to protected directories in acceptEdits mode

Fixed

• Rate-limit dialog infinite loop that crashed sessions after hitting usage limits
• `--resume` causing full prompt-cache miss on first request for users with deferred tools, MCP servers, or custom agents (regression since v2.1.69)
• `Edit`/`Write` failing with "File content has changed" when PostToolUse format-on-save hooks rewrite files between consecutive edits
• `PreToolUse` hooks emitting JSON to stdout with exit code 2 not correctly blocking tool calls
• Collapsed search/read summary badge appearing multiple times in fullscreen scrollback during CLAUDE.md auto-load
• Auto mode ignoring explicit user boundaries ("don't push", "wait for X before Y") even when action was allowed
• Click-to-expand hover text nearly invisible on light terminal themes
• UI crash when malformed tool input reached permission dialog
• Headers disappearing when scrolling `/model`, `/config`, and selection screens
• PowerShell permission checks: trailing `&` background job bypass, `-ErrorAction Break` debugger hang, archive-extraction TOCTOU, parse-fail fallback deny-rule degradation

Improved

• Performance — Eliminated per-turn JSON.stringify of MCP tool schemas on cache-key lookup
• Performance — SSE transport now handles large streamed frames in linear time (was quadratic)
• Performance — SDK sessions with long conversations no longer slow down quadratically on transcript writes
• /resume all-projects — Now loads project sessions in parallel, improving load times for users with many projects

Changed

• `--resume` picker no longer shows sessions created by `claude -p` or SDK invocations
• Removed `Get-DnsClientCache` and `ipconfig /displaydns` from auto-allow list (DNS cache privacy)

Update Claude Code via your extension marketplace or view the full release notes.

Source: Claude Code