[Bug] Claude struggles with debugging front-end algorithms in C# large codebases (not that large for the case)

Bug Description
Cluade cannot handle an admin panel text editor with medium-simple complicity with simple diff-review, and cannot diagnose bugs correctly.
2 files, 1400 rows of с# + blazor code only. Technically it's only about algorithms, not Blazor. Drank all my blood with thinking and wrong conclusions. Gemini solved it in moments. It's not the first time Claude really stucks to debug (C#) front-end components since version 4.5, considering them as "working" and cannot debug bugs, even when you point to the simptoms.

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.1.58
• Feedback ID: f6054fb3-fc3f-489c-8ca1-c3a8949de30a

Errors

[{"error":"Error: Request was aborted.\n    at FO1 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:886:97915)\n    at FO1.next (<anonymous>)\n    at nDq (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6067:6672)\n    at nDq.next (<anonymous>)\n    at oDq (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6072:9109)\n    at processTicksAndRejections (node:internal/process/task_queues:103:5)\n    at runNextTicks (node:internal/process/task_queues:68:3)\n    at process.processTimers (node:internal/timers:538:9)\n    at async file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6067:6131\n    at async U08 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:887:2399)","timestamp":"2026-02-28T07:05:33.050Z"},{"error":"Error: Request was aborted.\n    at FO1 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:886:97915)\n    at FO1.next (<anonymous>)\n    at nDq (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6067:6672)\n    at nDq.next (<anonymous>)\n    at oDq (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6072:9109)\n    at process.processTicksAndRejections (node:internal/process/task_queues:103:5)\n    at async file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6067:6131\n    at async U08 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:887:2399)\n    at async GW6 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:6067:6101)\n    at async bR (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:3547:6638)","timestamp":"2026-02-28T07:19:37.274Z"},{"error":"AxiosError: Request failed with status code 401\n    at cx (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:90:1138)\n    at Unzip.<anonymous> (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:91:9825)\n    at Unzip.emit (node:events:520:35)\n    at endReadableNT (node:internal/streams/readable:1701:12)\n    at process.processTicksAndRejections (node:internal/process/task_queues:89:21)\n    at VL6.request (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:93:2132)\n    at process.processTicksAndRejections (node:internal/process/task_queues:103:5)\n    at async Tu9 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:1177:365)","timestamp":"2026-02-28T16:30:04.834Z"},{"error":"Error: String not found in file. Failed to apply edit.\n    at DF6 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:1935:726)\n    at kX1 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:1935:104)\n    at Object.zo4 [as renderToolUseRejectedMessage] (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:2724:133)\n    at CV4 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:2435:4923)\n    at N3 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:288:20890)\n    at P_ (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:288:39409)\n    at VC (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:288:50095)\n    at gF (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:288:86675)\n    at d16 (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:288:85644)\n    at fi (file:///C:/Users/NickDr/AppData/Local/nvm/v24.11.1/node_modules/@anthropic-ai/claude-code/cli.js:288:85466)","timestamp":"2026-02-28T16:42:03.509Z"}]