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

Bug Description
Keep getting this error when coming out of plan mode API Error: 400 messages.1.content.2: thinking or redacted_thinking blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response.

Environment Info

• Platform: darwin
• Terminal: WarpTerminal
• Version: 2.1.154
• Feedback ID: 46a39ff0-3db0-4ad7-9068-b66754708f55

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.1.content.2: `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_011CbVcJPqaiFCL2obNPQq1T\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:63816)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-28T20:37:07.863Z"}]