[Bug] Anthropic API Error: Cannot modify thinking blocks in resumed conversations

Bug Description
When resuming a conversation and sending a new message. Seeing this error:
API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.7.content.66: 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_011CVu7WQxn7h4mJToammxLt"}

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.0.61
• Feedback ID: 2d08b659-27e4-4d1e-b63b-427bc0264990

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.7.content.66: `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_011CVu7Uton3sLN8u1YqAV6k\"}\n    at V9.generate (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:106:10318)\n    at rT.makeStatusError (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:1283:2195)\n    at rT.makeRequest (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:1283:5419)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async Q71.model (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:10426)\n    at async Q71 (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:2064:3271)\n    at async pz9 (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:10580)\n    at async file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:3864\n    at async lo1 (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:1435:2037)\n    at async gXA (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:3834)","timestamp":"2025-12-08T11:06:42.789Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.7.content.66: `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_011CVu7WQxn7h4mJToammxLt\"}\n    at V9.generate (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:106:10318)\n    at rT.makeStatusError (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:1283:2195)\n    at rT.makeRequest (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:1283:5419)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async Q71.model (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:10426)\n    at async Q71 (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:2064:3271)\n    at async pz9 (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:10580)\n    at async file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:3864\n    at async lo1 (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:1435:2037)\n    at async gXA (file:///Users/sahilshah/.nvm/versions/node/v21.6.1/lib/node_modules/@anthropic-ai/claude-code/cli.js:4129:3834)","timestamp":"2025-12-08T11:07:03.014Z"}]