Streamable Stateless server should support streaming

[taobaorun]

Expected Behavior

A server that is fully stateless and does not support long-lived connections can still take advantage of streaming in this design.
For example, to issue progress notifications during a tool call:
When the incoming POST request is a CallToolRequest, server indicates the response will be SSE
Server starts executing the tool
Server sends any number of ProgressNotifications over SSE while the tool is executing
When the tool execution completes, the server sends a CallToolResponse over SSE
Server closes the SSE stream

modelcontextprotocol/modelcontextprotocol#206

Current Behavior

The current implementation can only return json

return ServerResponse.ok().contentType(MediaType.APPLICATION_JSON).body(jsonrpcResponse);

Context

[quaff]

If I understand correctly, It's possible to let Spring AI support progress notification for stateless transport if this proposal is accepted.

See https://docs.spring.io/spring-ai/reference/1.1-SNAPSHOT/api/mcp/mcp-annotations-special-params.html#_usage_in_tools_2

[taobaorun]

If I understand correctly, It's possible to let Spring AI support progress notification for stateless transport if this proposal is accepted.

See https://docs.spring.io/spring-ai/reference/1.1-SNAPSHOT/api/mcp/mcp-annotations-special-params.html#_usage_in_tools_2

the sse or streamable stateful server（McpSyncServerExchange） can do it in this way, but stateless （McpStatelessSyncServer） ones cannot. Because stateless has no corresponding method

[quaff]

the sse or streamable stateful server（McpSyncServerExchange） can do it in this way, but stateless （McpStatelessSyncServer） ones cannot. Because stateless has no corresponding method

I understand currently it cannot, I'm wondering it will be supported in the future.