如何在agent内对LLM返回的流式function call参数进行合并？

流式返回大模型的function call的时候，返回的参数也是流式返回的

例如
- 第一个FunctionCall的arguments是{
- 第二个FunctionCall的arguments是"a" : "b"
- 第三个FunctionCall的arguments是}

需要拼在一起才是真实的参数，这个要如何拼接呢？文档里没看到有简单的方法

No file or test is named. Start by tracing the agent's streaming function-call handling and reading the tool-call documentation, then verify how fragmented arguments are represented and combined. Done means the supported approach is clear in the documentation, with an example covering the streamed fragments described here.

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