Create a Server

// Creating a server is a little more involved but the code is relatively straightforward

sse-server.rs
use mcp_core::{
    run_http_server,
    server::Server,
    sse::http_server::Host,
    tool_error_response, tool_text_response,
    types::{CallToolRequest, CallToolResponse, ServerCapabilities, Tool, ToolResponseContent},
};
use serde_json::json;
use thiserror::Error;

#[derive(Debug, Error)]
enum PostDmError {
    #[error("Missing data")]
    MissingData,
}

#[tokio::main]
async fn main() -> Result<(), anyhow::Error> {
    tracing_subscriber::fmt()
        .with_max_level(tracing::Level::DEBUG)
        .with_writer(std::io::stderr)
        .init();

    run_http_server(
        Host {
            host: "127.0.0.1".to_string(),
            port: 8080,
            public_url: None,
        },
        None,
        |transport| async move {
            let mut server_builder = Server::builder(transport)
                .capabilities(ServerCapabilities {
                    tools: Some(json!({
                        "listChanged": false,
                    })),
                    ..ServerCapabilities::default()
                })
                .version("0.1.0")
                .name("Example SSE Server");

            server_builder.register_tool(
                Tool {
                    name: "test".to_string(),
                    description: Some("Test Tool".to_string()),
                    input_schema: json!({
                       "type":"object",
                       "properties":{
                          "test_data":{
                             "type": "string",
                             "description": "Test data",
                          }
                       },
                       "required":["test_data"]
                    }),
                },
                move |req: CallToolRequest| {
                    Box::pin(async move {
                        let args = req.arguments.unwrap_or_default();
                        let data = args.get("test_data");

                        if data.is_none() {
                            return tool_error_response!(PostDmError::MissingData);
                        };

                        tool_text_response!(json!(data).to_string())
                    })
                },
            );

            Ok(server_builder.build())
        },
    )
    .await?;

    Ok(())
}