Summary

Generation fails in the desktop app on Windows 11 when using a relay/proxy-style model configuration. The app shows a modal error from the codesign:v1:generate IPC call:

Error invoking remote method 'codesign:v1:generate': CodesignError: 404 404 page not found

Environment

• OS: Windows 11
• App: Open CoDesign desktop
• App version shown in screenshot: v0.1.3
• Language: ZH UI
• Model/provider configuration shown: custom/custom-2edi, opus-4-6
• Network/model access path: relay/proxy setup (user report: 用中转报错了)

Steps to Reproduce

1. Open the desktop app on Windows 11.
2. Configure/select the custom relay model setup shown in the top bar.
3. Enter a prompt, for example:

Design a small showcase page presenting six organic loading indicators...

4. Start generation.

Actual Result

Generation fails and the app displays:

生成失败
生成过程中出错了。
Error invoking remote method 'codesign:v1:generate': CodesignError: 404 404 page not found

The same error also appears in the chat/error bubble on the left.

Expected Result

Generation should either succeed through the configured relay endpoint or show a more actionable configuration/network error explaining which endpoint/model route returned 404.

Notes

• Screenshot is available from the reporter conversation, but not attached here as a local file.
• Diagnostics bundle is not available yet. Per contributing guidance, this should be supplemented with Settings -> Storage -> Export diagnostics if the reporter can reproduce locally.
• This may be related to relay endpoint path/model-name translation, provider routing, or error normalization for 404 responses from custom providers.