Add MCP SDK based on rmcp

Author: byeblack

Cargo.lock

@@ -35,6 +35,7 @@ quick-xml = { version = "0.37.2", optional = true }
 rayon = { version = "1.10.0", optional = true }
 worker = { version = "0.5", optional = true }
 mcp-core = { version = "0.1.42", optional = true }
+rmcp = { version = "0.1.5", features = ["client"], optional = true }
 bytes = "1.9.0"
 async-stream = "0.3.6"
 mime_guess = { version = "2.0.5" }
@@ -51,6 +52,12 @@ serde_path_to_error = "0.1.16"
 base64 = "0.22.1"
 mcp-core = { version = "0.1.42", features = ["sse"] }
 mcp-core-macros = { version = "0.1.1" }
+rmcp = { version = "0.1.5", features = [
+    "server",
+    "client",
+    "transport-sse-server",
+    "transport-sse",
+] }
 
 [features]
 default = ["reqwest/default"]
@@ -63,6 +70,7 @@ epub = ["dep:epub", "dep:quick-xml"]
 rayon = ["dep:rayon"]
 worker = ["dep:worker"]
 mcp = ["dep:mcp-core"]
+rmcp = ["dep:rmcp"]
 socks = ["reqwest/socks"]
 # Replace "default-tls" with "rustls-tls" in "reqwest/default"
 reqwest-rustls = [
@@ -120,6 +128,10 @@ required-features = ["derive"]
 name = "mcp_tool"
 required-features = ["mcp"]
 
+[[example]]
+name = "mcp_tool_with_rmcp"
+required-features = ["rmcp"]
+
 [[example]]
 name = "openai_audio_generation"
 required-features = ["audio"]

rig-core/Cargo.toml

@@ -0,0 +1,71 @@
+use anyhow::Result;
+use rig::{
+    completion::Prompt,
+    providers::{self},
+};
+use rmcp::{
+    model::{CallToolResult, Content},
+    tool,
+    transport::{SseServer, SseTransport},
+    Error as McpError, ServerHandler, ServiceExt,
+};
+
+#[derive(Clone)]
+struct McpController;
+
+#[tool(tool_box)]
+impl McpController {
+    #[tool(name = "Add", description = "Adds two numbers together.")]
+    async fn add_tool(
+        #[tool(param)]
+        #[schemars(description = "The first number to add")]
+        a: f64,
+        #[tool(param)]
+        #[schemars(description = "The second number to add")]
+        b: f64,
+    ) -> Result<CallToolResult, McpError> {
+        Ok(CallToolResult::success(vec![Content::text(
+            (a + b).to_string(),
+        )]))
+    }
+}
+
+#[tool(tool_box)]
+impl ServerHandler for McpController {}
+
+#[tokio::main]
+async fn main() -> Result<(), anyhow::Error> {
+    tracing_subscriber::fmt().init();
+
+    // Create the MCP server
+    let serve_ct = SseServer::serve("127.0.0.1:3000".parse()?)
+        .await?
+        .with_service(|| McpController);
+
+    // Create the MCP client
+    let transport = SseTransport::start("http://127.0.0.1:3000/sse").await?;
+    let mcp_client = None.serve(transport).await?;
+
+    let tools_list_res = mcp_client.list_all_tools().await?;
+    println!("Tools: {:?}", tools_list_res);
+
+    tracing::info!("Building RIG agent");
+    let completion_model = providers::openai::Client::from_env();
+    let mut agent_builder = completion_model.agent("gpt-4o");
+
+    // Add MCP tools to the agent
+    agent_builder = tools_list_res
+        .into_iter()
+        .fold(agent_builder, |builder, tool| {
+            builder.mcp_tool(tool, mcp_client.clone())
+        });
+    let agent = agent_builder.build();
+
+    tracing::info!("Prompting RIG agent");
+    let response = agent.prompt("Add 10 + 10").await?;
+    tracing::info!("Agent response: {:?}", response);
+
+    serve_ct.cancel();
+
+    Ok(())
+}

rig-core/examples/mcp_tool_with_rmcp.rs

@@ -9,6 +9,9 @@ use crate::{
 #[cfg(feature = "mcp")]
 use crate::tool::McpTool;
 
+#[cfg(feature = "rmcp")]
+use crate::tool::McpTool;
+
 use super::Agent;
 
 /// A builder for creating an agent
@@ -118,6 +121,15 @@ impl<M: CompletionModel> AgentBuilder<M> {
         self
     }
 
+    // Add an MCP tool to the agent
+    #[cfg(feature = "rmcp")]
+    pub fn mcp_tool(mut self, tool: rmcp::model::Tool, client: rmcp::service::ServerSink) -> Self {
+        let toolname = tool.name.clone();
+        self.tools.add_tool(McpTool::from_mcp_server(tool, client));
+        self.static_tools.push(toolname.to_string());
+        self
+    }
+
     /// Add some dynamic context to the agent. On each prompt, `sample` documents from the
     /// dynamic context will be inserted in the request.
     pub fn dynamic_context(