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

Bug Description
API Error: 400 messages.3.content.17: 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: vscode
• Version: 2.1.154
• Feedback ID: 0417ff38-d9e2-4db4-b336-0a036febf063

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.3.content.17: `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_011CbVWwiZJ24BxaqRS3A92z\"}\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":"2026-05-28T19:26:53.688Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.3.content.17: `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_011CbVWyRvUtsQob9mb9XcmY\"}\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":"2026-05-28T19:27:16.558Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.3.content.17: `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_011CbVWzM8mqhUFz8ViMu8Nz\"}\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":"2026-05-28T19:27:29.033Z"}]