Claude Code v2.1.176 to v2.1.177 Major Updates - Suspension of access to Claude Fable 5 for all users

This is Ishikawa from the Cloud Business Division. Here is a summary of the Claude Code updates for v2.1.176 ~ v2.1.177 (2026-06-12 ~ 2026-06-13).

Please note that as a result of a US government directive, we have temporarily suspended access to Claude Fable 5 for all users.

https://www.anthropic.com/news/fable-mythos-access

https://x.com/ClaudeDevs/status/2065597942602531163

When launching Claude Code, even if you select Claude Fable 5 in the model selection, it will be switched to Claude Opus 4.8.

Update Summary

This covers 2 versions (v2.1.176 · v2.1.177, 2026-06-12 ~ 2026-06-13). While new features and improvements are included, the main focus of the updates is stabilization around background sessions, Remote Control, and model control. Within the scope we were able to confirm, the majority of the total 22 changes were bug fixes.

Note that v2.1.177 is published on npm, but at the time of writing this article, there is no record of changes in the official CHANGELOG, so this summary focuses primarily on the confirmed content of v2.1.176.

Notable Updates

• New Feature: A footerLinksRegexes setting has been added to display link badges in the footer row matched by regular expressions (v2.1.176)
• Bug Fix: An issue where connecting via Remote Control from web/mobile would implicitly switch the session's model has been fixed (v2.1.176)
• Security: The availableModels allowlist enforcement has been fixed, closing the path that allowed bypassing blocked models via environment variables (v2.1.176)

Target Versions and Period

New Features

• Addition of footerLinksRegexes setting: Link badges matched by regular expressions can now be displayed in the footer row. This can be configured from either user settings or managed settings (v2.1.176).

Improvements

• Language support for session titles: Session titles are now generated in the language used in the conversation. If you want to fix it to a specific language, specify the language setting (v2.1.176).
• Improved credential caching for Bedrock: Credentials obtained from awsCredentialExport are now retained until the credential Expiration, rather than the previous fixed 1 hour. For environments using Amazon Bedrock, credential refresh frequency will now align with the actual expiration time (v2.1.176).
• Enhanced guidance for background sessions: Clearer guidance is now displayed when a window has been kept open across automatic updates and a reply cannot be sent. Additionally, claude daemon status now explains behavior when version skew occurs (v2.1.176).

Security · Model Governance

• Fixed availableModels allowlist enforcement: Alias model selection will no longer be redirected to blocked models via ANTHROPIC_DEFAULT_*_MODEL environment variables. Additionally, /fast will now refuse to toggle when it would switch to a model outside the allowlist. This is an important fix for organizations restricting models with availableModels, as it closes paths that could bypass the allowlist (v2.1.176).

Fixes (Major)

Here is a selection focusing on fixes related to stability and operability.

• Fixed auto mode failure with Fable 5: Fixed an issue where auto mode would fail on Fable 5 in organizations where Opus 4.8 is not enabled. The classifier will now fall back to the best available Opus model (v2.1.176).
• Fixed path matching for hook if conditions: Fixed hook if conditions for paths in Read/Edit/Write tools, so that documented patterns such as Edit(src/**), Read(~/.ssh/**), and Read(.env) now match correctly (v2.1.176).
• Fixed copy/paste over tmux: Fixed an issue where /copy and mouse selection copy inside tmux over SSH would not reach the system clipboard, and an issue where paste buffers were not read in tmux versions prior to 3.2 (v2.1.176).
• Fixed implicit model switching in Remote Control: Fixed an issue where connecting via Remote Control from web/mobile would implicitly switch the session's model (v2.1.176).
• Fixed git branch display after /cd · worktree navigation: Fixed an issue where the session would continue to display the git branch of the previous directory even after moving via /cd or worktree navigation (v2.1.176).
• Fixed "Working" display for background sessions: Fixed an issue where a backgrounded session would continue to display "Working" when there was no remaining processing to continue after /bg mid-turn (v2.1.176).
• Fixed authentication errors for idle cloud sessions: Fixed an issue where cloud sessions that had been idle for a long time before claiming would fail with "Could not resolve authentication method" (v2.1.176).
• In addition, numerous minor bugs have been fixed including Linux sandbox startup, Remote Control disconnect notifications and disconnection on account switching, claude agents window operations and search, cursor display and daemon startup on Windows, and background session restart processing (v2.1.176).

Breaking Changes · Deprecations

There are no breaking changes or deprecation items in this target range (v2.1.176 · v2.1.177).

Closing

v2.1.176 was an update that included new features and improvements, while primarily focusing on stabilization around background sessions, Remote Control, and model control. In particular, the fix to availableModels allowlist enforcement is an important point for organizations operating with model restrictions. v2.1.177 has been published, but since there is currently no record of changes in the official CHANGELOG, it is recommended to check again once the content is made available. If there are any changes of interest, please try updating and checking them out.

References

https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md

https://code.claude.com/docs/en/changelog