Deepseek API 400 error when role=tool

[hqsow]

[ { "role": "user", "content": "请阅读我的文档" }, { "role": "assistant", "content": "我来帮您读取当前的文档内容。", "tool_calls": [ { "id": "call_00_IhNDqplrzL8xiABtVfI2K7hz", "name": "ReadDoc", "arguments": "{\"format\": \"structured\"}" } ] }, { "role": "tool", "content": "xxxx", "tool_call_id": "call_00_IhNDqplrzL8xiABtVfI2K7hz" } ]

以上 messages 发送到 deepseek api 必报400，但是一把 role:tool 改成 role:user 就能正常，请问是为什么？
难道deepseek不支持role=tool?不应该啊，我看官网文档自已都有用

400 error happens when The above message was send to Deepseek API, but it works when change role:tool to role:user, whY?