Building a Personal MCP Server for Claude

I’m tired of pasting my "about me" blurb every time I start a new chat with Claude. If you’re a developer using Claude for Desktop, you should be using the Model Context Protocol (MCP). It’s an open standard that lets AI models interact with your local data and tools through a unified interface.

Instead of generic context, we’re going to build a personal MCP server in TypeScript. This server will act as a dedicated knowledge base for your bio, active projects, and technical stack. When you ask Claude "What should I work on next?", it will actually know what's in your active_projects.json.

The Stack

We’re keeping this lean. No databases, no complex auth. Just a local Node.js process talking to Claude over stdio.

• Language: TypeScript
• Runtime: Node.js (v18+)
• SDK: @modelcontextprotocol/sdk
• Validation: zod

1. Project Setup

Start by initializing a new TypeScript project. The MCP SDK uses ESM, so make sure your package.json reflects that.

mkdir my-personal-mcp && cd my-personal-mcp
npm init -y
npm install @modelcontextprotocol/sdk zod
npm install -D typescript @types/node tsx

Update your package.json to include "type": "module" and a build script. Your tsconfig.json should target ES2022 or higher.

2. Define Your Data

Create a data.json file. This is where your personal context lives. Storing it as JSON makes it trivial for the MCP server to parse and serve to the LLM.

{
  "bio": "Full-stack developer focused on SaaS and open-source tools.",
  "tech_stack": ["TypeScript", "Next.js", "PostgreSQL", "FastAPI"],
  "projects": [
    {
      "name": "ArbindBuilds",
      "status": "active",
      "description": "A content system for indie makers."
    }
  ]
}

3. The Server Implementation

The core logic happens in src/index.ts. We use McpServer to register a tool. This tool will read our JSON file and return the contents to Claude.

import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { readFileSync } from "fs";
import { resolve } from "path";

// 1. Initialize the server
const server = new McpServer({
  name: "personal-context-server",
  version: "1.0.0",
});

// 2. Register the tool
server.tool(
  "get_personal_info",
  "Retrieves bio, projects, and tech stack information about Arbind",
  {}, // No arguments needed for this basic call
  async () => {
    try {
      const dataPath = resolve(process.cwd(), "data.json");
      const data = JSON.parse(readFileSync(dataPath, "utf-8"));
      
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(data, null, 2),
          },
        ],
      };
    } catch (error) {
      return {
        content: [{ type: "text", text: "Error: Could not read personal data." }],
        isError: true,
      };
    }
  }
);

// 3. Connect using stdio transport
async function main() {
  const transport = new StdioServerTransport();
  await server.connect(transport);
  console.error("Personal MCP server running on stdio");
}

main().catch((err) => {
  console.error("Fatal error:", err);
  process.exit(1);
});