[BUG] Missing Thinking Summary Blocks in the Claude AI Web Interface
Preflight Checklist
- [x] I have searched existing issues and this hasn't been reported yet
- [x] This is a single bug report (please file separate reports for different bugs)
- [x] I am using the latest version of Claude Code
What's Wrong?
Date/Time Observed: July 23, 2026, at approximately 5:00 AM UTC
Platform/Environment: Claude AI Website
Models Affected: All Models
Description
The thinking summary blocks disappeared from the chat interface starting on July 23, 2026. Previously, these blocks appeared before the generated text to show the reasoning process. Currently, no reasoning or thinking summaries are visible during or after generation, regardless of the model selected.
What Should Happen?
Expected Behavior
The interface displays an expandable thinking block showing the reasoning summary before the final response appears.
Actual Behavior
The chat interface goes into thinking in the background without showing a summary of what the model was thinking. The thinking summary block is completely missing from the screen.
Error Messages/Logs
Steps to Reproduce
Steps to Reproduce
- Log into the Claude AI web interface.
- Select any model with reasoning capabilities (Sonnet 4.6, Sonnet 5, or Opus).
- Send a message to the chat.
- Watch the response generation.
<img width="720" height="799" alt="Image" src="https://github.com/user-attachments/assets/ac109149-4ccd-47e6-a975-f8ad75fb6db2" />
Claude Model
Not sure / Multiple models
Is this a regression?
Yes, this worked in a previous version
Last Working Version
_No response_
Claude Code Version
2.1.218
Platform
Other
Operating System
Windows
Terminal/Shell
Windows Terminal
Additional Information
Use Case and Impact
I use the thinking block summaries to read how the model interprets my questions in real time. Seeing the initial reasoning process allows me to catch misunderstandings early. I can then stop or edit my prompt before the text generation finishes. The absence of this feature removes my ability to course-correct, leading to wasted time and causing message limits to be used up faster through multiple rerolls.