OpenAI API: Unexpected Opus 4 Availability Restriction in Pro Plan

Bug Description
It tells me that Opus 4 is not available with the Pro plan, but I want to use Sonnet. I don't know why it's using Opus when I already know that Opus isn't included in the Pro plan.

Environment Info

• Platform: linux
• Terminal: kitty
• Version: 1.0.44
• Feedback ID: 5878b2a5-d162-4429-ac91-aabe87d4e070

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"system: Invalid model name\"}}\n    at D6.generate (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1304:12578)\n    at gq.makeStatusError (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1321:2100)\n    at gq.makeRequest (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1321:5311)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)\n    at async fA1.showErrors (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:23214)\n    at async fA1 (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:12720)\n    at async aR2 (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:23062)\n    at async file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:18138\n    at async Y0A (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:5121)\n    at async Vc (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:18108)","timestamp":"2025-07-08T15:43:36.096Z"},{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"system: Invalid model name\"}}\n    at D6.generate (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1304:12578)\n    at gq.makeStatusError (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1321:2100)\n    at gq.makeRequest (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1321:5311)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)\n    at async fA1.showErrors (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:23214)\n    at async fA1 (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:12720)\n    at async aR2 (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:23062)\n    at async file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:18138\n    at async Y0A (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:5121)\n    at async Vc (file:///home/samuelg/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js:1690:18108)","timestamp":"2025-07-08T15:45:01.578Z"}]