[Bug] Anthropic API Error: Duplicate Tool Names in Request

Bug Description
100% repro on following bug - "error":{"type":"invalid_request_error","message":"tools: Tool names must be unique."}

To reproduce

• Unzip this zip file (creates claude-bug) directory
• run claude from claude-bug directory
• ask "Use the task tool to ask haiku what 1+1 is"
• Expected: answer of 2
• Observed: "Tool names must be unique" error

claude-bug.zip

Environment Info

• Platform: linux
• Terminal: kitty
• Version: 2.0.30
• Feedback ID: 6f4f5906-4be4-42ca-8efd-70ed987db402

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"tools: Tool names must be unique.\"},\"request_id\":\"req_011CUftxDNhwdJbkYcLFyC1E\"}\n    at generate (/$bunfs/root/claude:379:26098)\n    at makeRequest (/$bunfs/root/claude:524:5345)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-10-31T20:20:13.054Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at wf (/$bunfs/root/claude:1118:3185)\n    at map (native:1:11)\n    at j5 (/$bunfs/root/claude:1118:2902)\n    at mVI (/$bunfs/root/claude:1730:6532)\n    at oU (/$bunfs/root/claude:99:19415)\n    at zn (/$bunfs/root/claude:101:42816)\n    at qB (/$bunfs/root/claude:101:38357)\n    at Bu (/$bunfs/root/claude:101:38285)\n    at Ew (/$bunfs/root/claude:101:38139)\n    at rC (/$bunfs/root/claude:101:35218)","timestamp":"2025-10-31T20:20:21.330Z"},{"error":"Error: Request was aborted.\n    at makeRequest (/$bunfs/root/claude:524:3850)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-10-31T20:21:05.686Z"},{"error":"Error: Request was aborted.\n    at makeRequest (/$bunfs/root/claude:524:3850)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-10-31T20:22:33.006Z"}]