Claude Code 2.1.166 release notes

Version

2.1.166

Released

6 June 2026

Status

Stable release

What's new in Claude Code 2.1.166

The official notes for Claude Code 2.1.166 list 21 changes: 2 new features, 14 fixes and 5 other changes.

• 2 new features
• 14 fixes
• 5 other changes

Highlights

• new feature Added fallbackModel setting to configure up to three fallback models tried in order when the primary model is overloaded or…
• new feature Added glob pattern support in deny rule tool-name position ("*" denies all tools); allow rules reject non-MCP globs, and unknown…
• fix Fixed a recurring "image could not be processed" error and extra token usage when an unprocessable image was sent in…
• fix Fixed remote sessions becoming permanently stuck when a brief backend disruption occurred during worker registration at startup
• fix Fixed flickering in JetBrains IDE terminals (IntelliJ, PyCharm, WebStorm, etc.) on 2026.1+ by enabling synchronized output

Our short summary: changes are counted and classified automatically from the official notes, and highlights are shortened. The complete, authoritative list is in the official release notes on GitHub.

Full release notes on GitHub (Claude Code 2.1.166)

All Claude Code release notes · All releases

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