Subagents Cannot Use Third-Party Model Providers

Background tasks or spawned subagents cannot use third-party model providers. They are limited to the default models included with the user’s GitHub Copilot subscription, and there is currently no way to assign a custom model to subagents.

Because I have reached my GitHub Copilot model quota and switched to a third-party provider as an alternative, I am no longer able to spawn subagents.

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| Field | Value |
| --- | --- |
| App version | 1.0.26 |
| OS | macOS 27.0.0 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 3 |

该 issue 指出了 /chat 路径，涉及后台任务或已生成的 subagents。首先跟踪 subagents 的模型选择是如何配置的，以及第三方 provider 是如何表示的，然后确定分配自定义 provider 所需的设计。完成的标准是，已生成的 subagents 可以使用选定的第三方模型，而不是只能使用订阅的默认模型。

由索引模型根据 Issue 内容生成。