[Bug] Degraded Code Generation Accuracy and Instruction Following

Bug Description
I'm not even sure where to begin, other than to express just how increasingly frustrating Claude Code has been the last couple of weeks. I think I started using it about 4 weeks ago and it was like a miracle. Now I have to fight tooth and nail for any scrap of productivity. Just now I asked him to put some debug statements at certain points of a dispatcher file, and he simply put them in a completely different file that was useless to me. "You're absolutely right - I completely failed to follow your instructions. You asked for debug statements in the DISPATCHER (dispatcher_api.py), not the blob_processor." These things happen virtually on every prompt. It was not like this just a few weeks ago.

Environment Info

• Platform: win32
• Terminal: vscode
• Version: 1.0.113
• Feedback ID: 9438e073-9b24-4a6d-8626-52ab6cbc8c8c

Errors

[{"error":"Error: String not found in file. Failed to apply edit.\n    at SS (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1838:728)\n    at Object.renderToolUseRejectedMessage (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1902:2333)\n    at ezB (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:3026:1722)\n    at rD (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:84:19415)\n    at fl (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:42814)\n    at H9 (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38355)\n    at nf (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38283)\n    at WC (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38137)\n    at JH (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:35216)\n    at sB (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:84:4841)","timestamp":"2025-09-16T16:39:06.548Z"},{"error":"Error: String not found in file. Failed to apply edit.\n    at SS (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1838:728)\n    at Object.renderToolUseRejectedMessage (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1902:2333)\n    at ezB (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:3026:1722)\n    at rD (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:84:19415)\n    at fl (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:42814)\n    at H9 (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38355)\n    at nf (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38283)\n    at WC (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38137)\n    at JH (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:35216)\n    at sB (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:84:4841)","timestamp":"2025-09-16T16:40:41.594Z"},{"error":"Error: Tab close: Invalid tab not found!\n    at A3B (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1886:15963)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)\n    at async ntB (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:3600:19997)\n    at async AbortSignal.J (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:3600:18977)","timestamp":"2025-09-16T16:40:41.646Z"},{"error":"Error: String not found in file. Failed to apply edit.\n    at SS (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1838:728)\n    at Object.renderToolUseRejectedMessage (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:1902:2333)\n    at ezB (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:3026:1722)\n    at rD (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:84:19415)\n    at fl (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:42814)\n    at H9 (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38355)\n    at nf (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38283)\n    at WC (file:///C:/Users/steve/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:86:38137)\n    at JH (file:///C:/Users/steve/AppData/R

Note: Error logs were truncated.