`tasks/get` response deserialized as `CreateTaskResult` instead of `GetTaskInfoResult`

[coinmoles]

Describe the bug
CreateTaskResult and GetTaskInfoResult have near-identical structures:

rust-sdk/crates/rmcp/src/model/task.rs

Lines 65 to 67 in 32a68aa

	pub struct CreateTaskResult {
	pub task: Task,
	}

rust-sdk/crates/rmcp/src/model.rs

Lines 2050 to 2053 in 32a68aa

	pub struct GetTaskInfoResult {
	#[serde(skip_serializing_if = "Option::is_none")]
	pub task: Option<crate::model::Task>,
	}

This causes tasks/get responses to be deserialized as CreateTaskResult instead of GetTaskInfoResult.

To Reproduce
Steps to reproduce the behavior:

1. Send the tasks/get request.

let client = // Client initialization logic.
let server_result: ServerResult = client
    .send_request(ClientRequest::GetTaskInfoRequest(GetTaskInfoRequest {
        method: GetTaskInfoMethod,
        params: GetTaskInfoParams {
            meta: None,
            task_id: task_id.clone(),
        },
        extensions: Extensions::default(),
    }))
    .await?; // `server_result` is `ServerResult::CreateTaskResult`

Expected behavior
server_result should be ServerResult::GetTaskInfoResult

Additional context
I am using the latest commit (32a68aa) because the published version 0.14.0 does not include the enum-variant reordering fix.

rmcp = { git = "https://github.com/modelcontextprotocol/rust-sdk", features = ["macros", "client", "rmcp/transport-streamable-http-client-reqwest"] }

One possible solution would be to simply do:

match server_result {
    ServerResult::CreateTaskResult(task_info) => GetTaskInfoResult {
        task: Some(task_info.task),
    },
    ServerResult::GetTaskInfoResult(task_info) => task_info,
    _ => return Err(ServiceError::UnexpectedResponse),
};

But this feels very unintuitive.

Personally, I am not a huge fan of how a single enum is used for all possible requests/responses. I do not know how this could be fixed properly without changing that.

[coinmoles]

I have ran into another deserialization error of the same caliber: GetTaskInfoResult { task: None } deserializes as EmptyResult

Client code:

let task_info = match server_result {
    ServerResult::CreateTaskResult(task_info) => GetTaskInfoResult {
        task: Some(task_info.task),
    },
    ServerResult::GetTaskInfoResult(task_info) => task_info,
    _ => anyhow::bail!("Unexpected server result: {server_result:?}"),
};

Server logs:

2026-02-02T08:17:11.656604Z DEBUG serve_inner: rmcp::service: received request id=6 request=GetTaskInfoRequest(Request { method: GetTaskInfoMethod, params: GetTaskInfoParams { meta: None, task_id: "1" }, extensions: Extensions })
2026-02-02T08:17:11.656986Z DEBUG serve_inner: rmcp::service: response message id=6 result=GetTaskInfoResult(GetTaskInfoResult { task: None })

Client logs:

Error: Unexpected server result: EmptyResult(EmptyObject)