[BUG] "invalid_request_error","message":"messages.213.content.0.type: Expected `thinking` or `redacted_thinking`, but found `text`.

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?

Fedora 43, GNU bash, version 5.3.0(1)-release (x86_64-redhat-linux-gnu), Claude Code v2.0.35 , thinking off.
This bug happened twice in my conversation, both times, if i wrote, again, /context, it worked.

/context

⎿ Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.213.content.0.type: Expected thinking or redacted_thinking, but found text. When thinking is enabled, a final assistant message must start with a thinking block. We recommend you include thinking blocks from previous turns. To avoid this requirement, disable thinking.
Please consult our documentation at https://docs.claude.com/en/docs/build-with-claude/extended-thinking"},"request_id":"req_011CUtix6MfZSXhdhtac6uVp"}

What Should Happen?

/context

Context Usage
...

Error Messages/Logs

first time:
> /context 
  ⎿ Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.109.content.0.type: Expected `thinking` or `redacted_thinking`, but found `text`. When `thinking` 
    is enabled, a final `assistant` message must start with a thinking block (preceeding the lastmost set of `tool_use` and `tool_result` blocks). We recommend you include thinking blocks 
    from previous turns. To avoid this requirement, disable `thinking`. Please consult our documentation at 
    https://docs.claude.com/en/docs/build-with-claude/extended-thinking"},"request_id":"req_011CUtVPxfeUMqhHtFrYGsUS"}


second time:
> /context 
  ⎿ Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.213.content.0.type: Expected `thinking` or `redacted_thinking`, but found `text`. When `thinking`  is enabled, a final `assistant` message must start with a thinking block. We recommend you include thinking blocks from previous turns. To avoid this requirement, disable `thinking`. 
    Please consult our documentation at https://docs.claude.com/en/docs/build-with-claude/extended-thinking"},"request_id":"req_011CUtix6MfZSXhdhtac6uVp"}

Steps to Reproduce

at the beginning of the session i was using thinking mode on. then i toggled it off.
the first time i used /context it gave me this error, i tried again right after and it worked.
after a few hours i used /context again and it gave me this error again, i tried again right after and it worked.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.0.35

Platform

Anthropic API

Operating System

Other Linux

Terminal/Shell

Other

Additional Information

_No response_