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

Bug Description
I'm getting "API Error: 400 messages.13.content.9: thinking or redacted_thinking blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response." constantly on my session.

Environment Info

• Platform: linux
• Terminal: ghostty
• Version: 2.1.149
• Feedback ID: 8b1ac617-6fa0-4a12-a144-8fb2a5294f51

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.13.content.9: `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_011CbZfewaTxo2gYLCWQsFjW\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:63341)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-31T00:03:29.925Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.13.content.9: `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_011CbZfh4jdXtH6iFjoSEuPk\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:63341)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-31T00:03:58.836Z"}]