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

Bug Description
API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.5.content.48: 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_011CXgqVpDWf3P699YRSz4QD"}

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.1.29
• Feedback ID: d36b6d02-3c22-4fa0-ba95-194b7d83b90b

Errors

[{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at QXT (/$bunfs/root/claude:2872:20450)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:27.887Z"},{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at QXT (/$bunfs/root/claude:2872:20450)\n    at async Q (/$bunfs/root/claude:3810:13772)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:28.802Z"},{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at QXT (/$bunfs/root/claude:2872:20450)\n    at async h (/$bunfs/root/claude:3810:14288)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:28.802Z"},{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at QXT (/$bunfs/root/claude:2872:20450)\n    at async Q (/$bunfs/root/claude:3810:13772)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:32.301Z"},{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at QXT (/$bunfs/root/claude:2872:20450)\n    at async h (/$bunfs/root/claude:3810:14288)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:32.301Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.5.content.48: `thinking` or `redacted_thinking` blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response.\"},\"request_id\":\"req_011CXgqUXsjDwcWMvu2rnkdi\"}\n    at generate (/$bunfs/root/claude:343:8698)\n    at makeRequest (/$bunfs/root/claude:360:5435)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:35.797Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"messages.5.content.48: `thinking` or `redacted_thinking` blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response.\"},\"request_id\":\"req_011CXgqVpDWf3P699YRSz4QD\"}\n    at generate (/$bunfs/root/claude:343:8698)\n    at makeRequest (/$bunfs/root/claude:360:5435)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-01T05:58:53.141Z"}]