catbox-mcp-server: Technical Breakdown

From zero to npm publish — a complete workflow for building an MCP server.

Project Structure

catbox-mcp-server/
├── index.js          # Main entry point
├── README.md         # English documentation
├── package.json      # npm configuration
└── LICENSE           # MIT

Core Code

// index.js - MCP server entry point
import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { CallToolRequestSchema, ListToolsRequestSchema } from "@modelcontextprotocol/sdk/types.js";
import FormData from "form-data";
import axios from "axios";

const CATBOX_API = "https://catbox.moe/user/api.php";

async function apiCall(params) {
  const form = new FormData();
  for (const [k, v] of Object.entries(params)) {
    if (v !== undefined && v !== null) form.append(k, v);
  }
  const res = await axios.post(CATBOX_API, form);
  return { result: res.data.trim() };
}

Publishing to npm

npm login
npm publish

Results

• npm: catbox-mcp-server v1.0.1
• GitHub: github.com/xxy9468615/catbox

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Tags: MCP, Tools, npm