Claude Code 2.1.156

May 28, 2026

This release primarily focuses on stability improvements. A significant bug has been resolved concerning Opus 4.8. Previously, unintended modifications to thinking blocks led to API errors, disrupting workflow. This fix ensures reliable API interactions for all users working with Opus 4.8, improving the overall development experience.

Fixed

Fixed an issue when using Opus 4.8 where thinking blocks were modified, leading to API errors.