When tools are unavailble the session just gets stuck in a loop of saying it ...

When tools are unavailble the session just gets stuck in a loop of saying it has done the work without actually doing anything. It should instead inform the user that something is broken and to try again later
(or even better the agent could periodically check if it can proceed similar to what it does with agent merge)

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| Field | Value |
| --- | --- |
| App version | 1.1.3 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Day 6 (Week 1) |

首先，在应用版本 1.1.3 中的 /chat 路径使用不可用的工具重现该问题，并观察会话如何处理工具失败。跟踪会话的工具可用性和完成处理；当它不再声称成功，并告知用户出现了问题或提供重试途径时，即表示完成。

由索引模型根据 Issue 内容生成。