[Bug] Anthropic API Error: Cannot modify thinking blocks in assistant message

Resolved 💬 3 comments Opened Dec 6, 2025 by ErnstTmp Closed Dec 10, 2025

Bug Description
The output is always the same error message no matter what I do:

hello

⎿  API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.1.content.62: thinking or redacted_thinking blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original
response."},"request_id":"req_011CVqKyfFtX8J1Xoh2D5kXd"}

Environment Info

  • Platform: darwin
  • Terminal: iTerm.app
  • Version: 2.0.60
  • Feedback ID: 645c5c12-4808-45ce-adc4-41c075ccf20f

Errors

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