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

Bug Description
randomly hitting "API Error: 400 messages.9.content.33: 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: 2.1.152
• Feedback ID: 72d3e137-1814-4ddf-8856-9d35a568a6a2

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.33: `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_011CbVJb1M7Hs6cRw4johfDs\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:63975)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-28T16:44:50.523Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.33: `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_011CbVJdbsovFmNgu9SfhXTM\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:63975)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-28T16:45:25.719Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.9.content.33: `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_011CbVJg1iL15TUUvMeGWNJg\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:63975)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-28T16:45:58.551Z"}]