@respan/instrumentation-mcp

Respan instrumentation plugin for the Model Context Protocol TypeScript SDK.

The package adds Respan spans for common MCP client operations and server-side tool handlers from @modelcontextprotocol/sdk.

Install

npm install @respan/respan @respan/instrumentation-mcp @modelcontextprotocol/sdk

Quickstart

import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { StdioClientTransport } from "@modelcontextprotocol/sdk/client/stdio.js";
import { Respan } from "@respan/respan";
import { MCPInstrumentor } from "@respan/instrumentation-mcp";

const respan = new Respan({
  instrumentations: [new MCPInstrumentor()],
});
await respan.initialize();

const transport = new StdioClientTransport({
  command: "node",
  args: ["server.js"],
});

const client = new Client({ name: "demo-client", version: "1.0.0" });
await client.connect(transport);

const tools = await client.listTools();
console.log(tools.tools.map((tool) => tool.name));

const result = await client.callTool({
  name: "summarize_city",
  arguments: { city: "Paris" },
});
console.log(result);

await respan.flush();

Captured Operations

• Client.connect()
• Client.listTools()
• Client.callTool()
• Client.listResources()
• Client.readResource()
• Client.listResourceTemplates()
• Client.listPrompts()
• Client.getPrompt()
• McpServer.registerTool() handlers
• McpServer.tool() handlers

Client tool calls and server tool handlers are emitted as tool spans. List, resource, prompt, and connect operations are emitted as task spans.