Agents SDK MCP Server with state based on URL

index.ts

import { McpAgent } from "agents/mcp";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";

type Props = {
  org: string;
  project: string;
};

type State = {
  org?: string;
  project?: string;
};

export class MyMCP extends McpAgent<Env, State, Props> {
  server = new McpServer({
    name: "MCP Server with Props",
    version: "1.0.0",
  });

  async init() {
    // Only set if not already set (ie, first request for session)
    if (this.state?.org == null) {
      this.setState(this.props);
    }
    this.server.tool("whoami", async () => ({
      content: [
        {
          type: "text",
          text: `Org: ${this.state.org}, Project: ${this.state.project}`,
        },
      ],
    }));
  }
}

export default {
  fetch(request: Request, env: Env, ctx: ExecutionContext) {
    const url = new URL(request.url);

    if (url.pathname === "/sse" || url.pathname === "/sse/message") {
      return MyMCP.serveSSE("/sse").fetch(request, env, ctx);
    }

    const pattern = new URLPattern({ pathname: "/mcp/:org?/:project?" });
    const result = pattern.exec(url);
    if (result) {
      const { groups } = result.pathname;

      ctx.props.org = groups?.org ?? "";
      ctx.props.project = groups?.project ?? "";

      return MyMCP.serve(pattern.pathname).fetch(request, env, ctx);
    }

    return new Response("Not found", { status: 404 });
  },
};