MCP tool not invoked when using streaming with .content()

When using streaming Q&A with the following code:

public Flux chat_v1(String chatId, String userMessageContent) {
return this.chatClient.prompt()
.user(userMessageContent)
.advisors(
).stream()
.content();
}

the MCP tool is triggered, but it does not actually execute.
Instead, the output looks like this:

<|pos_agent|>

Action : spring_ai_mcp_client_server1_simpleNl2Sql

Action Input : {"input":"查询 用户 人数"} <|eoc|>

The tool is recognized, but no real call is made.

The report provides no repository file or test; start from the chat_v1 entry point and trace the streaming .stream().content() path when the MCP action is emitted. Compare that path with the non-streaming tool-call flow, and verify completion when the MCP tool executes and returns its result instead of only printing the action text.