Model Selection Broken: Only GPT-5 Works - Claude Models Return "model_not_supported" Error #136
Description
Describe the bug
The Copilot CLI officially provides three model options (GPT-5, Claude4, and Claude4.5), but only GPT-5 is functional. Attempting to use either Claude model results in a model_not_supportederror, making the model selection feature effectively non-functional for 2/3 of the available options.
Affected version
0.0.330 Commit: a8bfefe
Steps to reproduce the behavior
Install and configure GitHub Copilot CLI
Attempt to switch to Claude4 model using appropriate command
Receive error: × Model call failed: {"message":"The requested model is not supported.","code":"model_not_supported","param":"model","type":"invalid_request_error"}
Repeat step 2 with Claude4.5 model - same error occurs
Switch back to GPT-5 - functionality restored
example：
Microsoft Windows [版本 10.0.26100.6584]
(c) Microsoft Corporation。保留所有权利。
C:\Windows\System32>npm install -g @github/copilot
added 5 packages in 7s
npm notice
npm notice New major version of npm available! 10.9.3 -> 11.6.1
npm notice Changelog: https://github.com/npm/cli/releases/tag/v11.6.1
npm notice To update run: npm install -g npm@11.6.1
npm notice
C:\Windows\System32>
C:\Windows\System32>
C:\Windows\System32>copilot
Welcome to GitHub Copilot CLI
Version 0.0.330 · Commit a8bfefe
Copilot can write, test and debug code right from your terminal. Describe a
task to get started or enter ? for help. Copilot uses AI, check for mistakes.
Windows support is experimental. If you encounter issues, consider running
Copilot inside Windows Subsystem for Linux (WSL). Please report any issues
using /feedback.
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ │
│ Do you trust the files in this folder? │
│ │
│ ╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮ │
│ │ C:\Windows\System32 │ │
│ ╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯ │
│ │
│ Copilot may read files in this folder. Reading untrusted files may lead Copilot to behave in unexpected ways. │
│ │
│ With your permission Copilot may execute files in this folder. Executing untrusted code is unsafe. │
│ │
│ This project also allows Copilot to automatically execute bash commands on your machine. │
│ │
│ > 1. Yes, proceed │
│ 2. Yes, and remember this folder for future sessions │
│ 3. No, exit (Esc) │
│ │
│ Confirm with number keys or ↑↓ keys and Enter, Cancel with Esc │
│ │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
Welcome to GitHub Copilot CLI
Version 0.0.330 · Commit a8bfefe
Copilot can write, test and debug code right from your terminal. Describe a
task to get started or enter ? for help. Copilot uses AI, check for mistakes.
Windows support is experimental. If you encounter issues, consider running
Copilot inside Windows Subsystem for Linux (WSL). Please report any issues
using /feedback.
● Connected to GitHub MCP Server
● Logged in as user: kaoIa
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ > 你好 │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
× Model call failed: {"message":"The requested model is not
supported.","code":"model_not_supported","param":"model","type":"invalid_request_error"}
● Operation cancelled by user
● Model changed to: gpt-5. The new model will be used for the next conversation.
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ > 你好 │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
● 你好！有什么我可以帮你的吗？
如果你在做一个项目或需要写代码、调试、查资料，都可以直接告诉我你的目标或问题。
随便说：
1. 想写什么语言的代码？
2. 想解决什么报错？
3. 想生成脚本/配置/测试用例？
告诉我你的需求，我们马上开始。
Expected behavior
All three officially listed models (GPT-5, Claude4, and Claude4.5 and so on) should be accessible and functional, allowing users to choose between different AI models based on their preferences and use cases.
Additional context
Operating system: Windows
The error suggests backend infrastructure may not be properly configured for Claude models
This significantly limits user choice and undermines the advertised multi-model capability
Users expecting Claude model functionality are unable to utilize these options